The correct option is B p-3, q- 1, r-4, s-2
The microsporangium of anther is surrounded by four wall layers – the epidermis, endothecium, middle layers and the tapetum. The outer three layers provide protection and also help in the dehiscence of anther.
Tapetum is the innermost wall layer of the microsporangium. It provides nourishment to the developing pollen grains.
Microspores are formed from pollen mother cell (PMC) through meiosis. The process of formation of microspores from a pollen mother cell is called microsporogenesis.
The outer layer of pollen grain called exine is made up of sporopollenin. It is a highly resistant material and cannot be degraded by any enzyme.