Dichotomous key ! i know how to make one sort of; this is my first time doing one. any is appreciated.

The study of interaction between living organisms and their enviroment is called (a) phytogeography (b) ecology (c) phytosociology (d) ecosystem

I’m stuck on this question cuz i’m stupid sksksksk

Consider the venn diagram of plant reproduction. where in this image, areas a - d, would you insert the picture of the orange lily?