If 2ab - c = 2a(b - c), which of the following must be true?  Choose the correct choice:
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=1/2 or c=0
2ab - c = 2a(b - c)   =&gt; 2ab - c = 2ab - 2ac   =&gt; - c = - 2ac   =&gt; c = 2ac   =&gt; c - 2ac = 0   =&gt; c (1 - 2a) = 0   Either c = 0 or 1 - 2a = 0 i.e. a = 1/2.   Hence, a=1/2 or c=0
<result>E</result>
If 2ab - c = 2a(b - c), which of the following must be true?