Plants that have many periods of reproduction are called annuals perennials gametophytes sporophytes

The answer to the question above is perrenials.
Perrenial plants live for more than a year. Annual plants live only for a year they germinate,  grow and bear flowers or seeds but eventually die. while both c and d, (gametophytes and sporophytes) are both phases of plant lifecycle, not a type of plant. 

D. china is one of the most active places, which could quite possibly mean more agriculture will happen.. and more war machi-    best of luck comrade.

Ibelieve the answer is relative humidity  because it makes more sense that way. solar flares usually occur in space it doesn't affect the earth, well it could but it wont make a significant damage.  latitude is land it doesnt do anything. prevailing winds, i dont know the correct meaning for this but i doubt that affects the land so it has to be relative humidity.