The correct option is
B Shorea
Shorea is a genus of about 196 species of mainly rainforest trees in the family.
General flowering is an event that occurs at irregular intervals of 3–10 yr, in which nearly all dipterocarp species together with species of other families bloom heavily. It is thought that general flowering evolved to satiate seed predators and/or to facilitate pollination.[4] It appears that both explanations hold merit. Flowering is thought to be triggered by droughts that occur during transition periods.
So the correct answer is 'Shorea'.