The walls of microsporangium which are responsible for protection are:
Pericarp, Epidermis and Tapetum
Epidermis, Testa and Tegmen
Epicarp, Epidermis and Epithelium
Epidermis, Endothecium and Middle layer
The outer three layers of the microsporangium i.e, Epidermis, Endothecium and Middle layer is responsible for protection.