In the darkness, she felt ________, but when she turned around, nobody was there.

A．to follow

B．following

C．to be followed

D．being followed

乳剂型软膏基质与口服乳的区别在于

A．油相中油脂类的熔点

B．乳化剂黏度大小

C．乳化温度

D．水相相容积分数的大小

E．乳化剂类型的不同