Which words get highlighted on the SD recent addition links?

On the SD front page, there’s a list with links to “recent additions” (sidekick question: Why are they marked “recent” if many of those columns have been published years ago?). I’ve noticed that the systematics (if there are any) of which words are highlighted int he links seems weird to me.
Take today’s links for example: There’s “Is liver good for you? Isn’t it full of pesticides?” among it. “Good” is highlighted. Why exactly “good?” I’d pick the central term of the phrase to be highlighted, and I think this would be “liver.”
I’ve considered maybe they highlight the term on which you’d put the stress when speaking the phrase, but doesn’t seem to work out.

Surely it’s a pointless minor question, but I’m just curious so I’d appreciate it if any of the SD people could tell me about your “policy” (if there is any) about that.

Because the column in question was recently featured on the front page.