Read the following SAT test question and then click on a button to select your answer.

4(x-2)+x=ax-8

If the equation has exactly one solution, which of the following could be the value of a?

I.3
II.5

A.NONE
B.I
C.II
D.I and II

来源:可可英语 http://www.kekenet.com/sat/201605/443226.shtml