Which one amongst the given perform the function of protection in typical microsporangium?

Which one amongst the given perform the function of protection in typical microsporangium?
(A) Epidermis                                                       (B) Endothecium

(C) Tapetum                                                          (D) Middle layer

Option 1 : A and B
Option 2 : A and C
Option 3 : A and D
Option 4 : A, B and D