Which of the Following Features Is Most Important for True

Which of the following features is most important for true mosses and ferns to reproduce in the desert?

A) that the sporophytes occupy only permanently shady, north-facing habitats
B) that the sporophytes hug the ground, growing no taller than a couple of inches
C) either that their gametophytes grow close together, or that they be hermaphroditic
D) that the sporophytes have highly lignified vascular tissues
E) that the gametophytes contain secondary compounds to deter herbivores