Which of the following best compares mosses and ferns?

a. They are both vascular plants, but mosses are gymnosperms and ferns are angiosperms.
b. They are both angiosperms, but mosses produce seeds and ferns produce spores.
c. They are both gymnosperms, but mosses have flagellated sperm and ferns do not.
d. They are both seedless, but mosses are nonvascular and ferns are vascular.