Must be true --> a3b = ab3

[Vemuri]

If ab ≠ 0 and a^3b = ab^3, then which of the following must be true?

a = b
a = –b
ab = 1

A. None
B. I only
C. III only
D. I and III only
E. I, II, and III

OA is A. Please explain with reasoning

[scoobydooby]

if a3b=ab3, then b must be 3.
the number must be of the form a33. a can take any value.

not necessary that a must be =b, -b or ab=1.
hence, A

[vittalgmat]

I dint even undersand the Question.
@Vemuri,
does a3b mean a-cubed * b?
and does ab3 mean a * b-cubed ?

[Vemuri]

I dint even undersand the Question.
@Vemuri,
does a3b mean a-cubed * b?
and does ab3 mean a * b-cubed ?

Oppsss...sorry guys. I copy pasted the question from a website & looks like the some characters went missing. I have corrected my original post.

Sorry for the confusion. I am generally careful when posting the questions, missed it out this time