What do the moss life cycle and the fern life cycle have in common

D) Fertilization produces a diploid cell.

Explanation:

In mosses;  A single spore germinates to form a branched, filamentous protonema, from which a leafy gametophyte develops. The gametophyte bears organs for sexual reproduction. Sperm, which are released by the mature antheridium (the male reproductive organ), are attracted into the neck of an archegonium (the female reproductive organ). Here, one sperm fuses with the egg (fertilization) to produce the diploid zygote.

The life cycle of a fern is very different from the life cycle of many other plants. Ferns have an intermediate stage, called a gametophyte, which then grows into a mature fern. During Gametophyte stge, the spores are produced on the underside of mature plants. These will germinate and grow into small, heart-shaped plants called gametophytes.  The gametophytes produce both sperm and egg cells, and will fertilize itself, or others to yield a diploid cell.

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.

i believe your answer would be c.. : )