.I got caught in the rain and was wet all over. _____I had followed my mother’s advice and take an umbrella with me!

A．As if

B．Even if

C．If only

D．Only if

区分肠杆菌科中致病菌与非致病菌最有价值的试验是（）

A.葡萄糖发酵试验

B.乳糖发酵试验

C.动力试验

D.革兰染色法

E.血清学试验