For me, the falsehood is the obvious choice. I don't particularly value truth as an end (or rather, I do, but there are ends I value several orders of magnitude more). The main reason to seek to have true beliefs if truth is not the end goal is to ensure that you have accurate information regarding how well you're achieving your goal. By ensuring that the falsehood is high-utility, that problem is fairly well utility.

My beliefs are nowhere near true anyway. One more falsehood is unlikely to make a big difference, while there is a large class of psychologically harmful truths that can make a large (negative) difference.