为什么猪喜欢拱土

你问我答:
下面哪种物品是根据猪嘴发明的:
A.防毒面具
B.口罩
C.头盔

BGM:
Ramin Djawadi - Beach of Namibia
Ramin Djawadi - Danny's Balloon (The March Land)
Ramin Djawadi - Going to Ngoro Ngoro
Alan Williams - Animal Montage
Alan Williams - RainSearching for Herbs