Let’s say it is the year 2050 and all of the logistic and financial constraints for delivering a crew of human colonists to Mars have been overcome, somehow.
It’s a one way trip for a couple of dozen colonists. Electrical power for the colony will not be a big problem, thanks to Mr Fusion, or whatever - so extraction of water and oxygen from local materials is possible. Heavy machinery and colony building materials will be supplied periodically from Earth, but the colony will have to be more or less self sufficient for food, indefinitely.
So… what’s actually on the menu? I think field-scale crops such as soy beans or wheat are probably impractical, as, most likely, is the notion of raising almost any kind of vertebrate livestock (although maybe catfish… except they probably need more water than all of the colonists put together).
The solution needs to be nutritionally complete. Maybe Earth can send consignments of trace nutrient pills, but pouches of dehydrated protein powder are not guaranteed. How will 24 adult humans be fed? Assume no magical GMOs or vat-grown steaks, beyond what is possible today.
Is it going to be algae, brine shrimp and crickets?