That misses the whole point.
The question is not “how to get a banana into a baby.”
The question is “how to get another person to do something.”
Unless you’re saying that you’d pick option Z: Never ask anybody to do anything. Do it all yourself. Get a martyr complex. And then at some later date, freak out and cry and make a scene about how you have to do everything yourself around here while the other people sit around going 
.
I’m definitely a D, tho I would phrase it “Would you please give the baby a banana.”
A and B drive me fucking nuts. You want me to do something, ask me. Don’t hint around, or act as tho my feelings and perceptions are - or ought to be - identical to yours.
I’m a diplomatic D, unless the situation calls for a lack of diplomacy.
A and B are too milquetoast and that makes me insane. Do something or tape it shut. Talking isn’t doing. If there’s a hungry baby, feed it.
I’m an B (first clause)/C:
B: I think the baby’s hungry. Would you mind giving her/him [the baby] a banana?
Wow. That was a lot of fancy projection and mind reading based on one line, especially after I’ve already posted that my general style is C. Did someone lay a lot of guilt trips on you and get your panties all in a twist? Why would I complain about something that I just chose to get up and do? Maybe you need to work this one out with your mother or girlfriend or whoever has you so worried.
If I ever get tired of my current sig line, may I use that?
In my world, the only proper response to A is “Yeah it does - so feed it already.”
Green Bean - you have my sympathies. I noticed you said EX. That is probably for the best.
C in my personal life. D at work, where it’s my job to tell people what to do.
This is passive-aggressive. I respond very poorly to passive-aggressive, and certainly don’t use it. If you want something from me, ask for it.
My response would be all of “Okay” while I continue about my business. And I would very politely continue to do so for as long as you wished to impart obvious information to me. I won’t alter my behavior until you actually ask me to (although by this time I may have already left, if my current business required it).
Somewhat better (specifically the I-referencing in the first sentence). The second sentence is still passive-aggressive. You clearly want me to do something with that banana, so why don’t you just come out and say what that is?
My response: “There’s a banana in the basket next to you.” “Yep. There is.”
I would personally revise this to a combination of B & C: “I think the baby’s hungry. Would you mind giving the baby a banana?” It I-references, imparts specific information to make the context of the request clear (baby is hungry), and the request is clearly stated as a request of a specific behavior I am asking you to perform. It’s polite, direct, doesn’t assume any entitlement, and gives you all the information you need to know.
Uhm, unless we’re engaged in a roleplay scene, you don’t have my permission to order me around. This is a very controlling and entitled way to “ask” (and it’s certainly a demand, and not a request). Depending on the person, my immediate response would range from “Ask nicely and I’ll consider it,” (if the person in question has already built up a lot of friendship credit with me already) to “No,” accompanied by walking out of the room.
It would also raise a red flag and cause me to scrutinize you very carefully over our next several encounters, so I can see if it was some sort of temporary insanity or your regular mode of interacting with others. If the latter, it ends our relationship, whatever it was.
You don’t use passive-aggressive, huh? 
Valete,
Vox Imperatoris
I don’t like to beat around the bush much so I try to be direct, sometimes brusque so I’ll say D. I do however take into account who I’m speaking with and what method would work best to get the result I want.
Nope. I don’t consider it passive-aggressive to make no attempt to mind-read. I was absent on the day they handed out telepathy. I respond to the information you give me. I think it’s rather rude to assume that I know what’s in your head without having been told, actually. It treads awfully close to making baseless accusations. The key here is that I have no way of knowing what you’re thinking unless you say it to me. I’m just not in the habit of looking for hidden shades of meaning (which in most cases aren’t even there – as I’m more likely to spend time with people who do know how to be direct) in every word that others say to me. I’ll take what you say at face value, thanks. Not going to make myself crazy second-guessing every word you say.
I can only go on what you tell me. If you tell me a statement of fact, I will acknowledge that I heard it. If you have not asked me for something, I’m not going to assume that you want it. I’m also not going to stop what I’m doing so I can try to puzzle out what you really meant. If you want me to understand, you have the option of communicating clearly, and I figure you will do so if you want to. That’s not my responsibility and I won’t take it on for you, nor will I cool my heels waiting for you when I’ve got other things I need to do. I won’t guess; it’s a waste of time and it’s probably 50/50 whether I’d even guess right.
It’s simply a stupid game that I refuse to play. I make a guess at what you want; I likely guess wrong; and then I get a shitload of drama for having done the wrong thing. The drama-free know how to be direct.
That said, I can usually twig to the passive-aggressiveness, if it is so, pretty quickly. It would still be pretty rude of me to start throwing out accusations. What if I’m just having a bad day and am reading way too much into it? If I continue to take what I’m told at face value, the other person will eventually clear up any confusion themselves, without any need for accusations on my part.
I also ask for what I want in the form of a direct question.
I will, however, also say that I resent if someone puts me in a position where I am clearly expected to read their mind, which is another reason why I won’t attempt to do so.