If 2ab - c = 2a(b - 2c), which of the following must be true?  Options:
A) a=0 and c=0
B) a=1/2 and b=2
C) b=1 and c=0
D) a=1 or b=0
E) a=1/4 or c=0
2ab-c = 2a (b-2c)   2ab - c = 2ab - 4ac   c= 4ac   4ac-c = 0   c(4a-1) = 0   a=1/4 or c=0ither c = 0; or a = 1/4   a=1/4 or c=0 is the answer
<result>E</result>
If 2ab - c = 2a(b - 2c), which of the following must be true?