I don't like wearing _______A.a long hair B.long hair C.long hairs为什么急

I don't like wearing _______A.a long hair B.long hair C.long hairs为什么
急

1、头发应该是不可数,所以C错误
2、根据语言习惯应该是a long hair(一头长发)
所以A选项正确