Help with a MATHS QUESTION?

Question

which of the following is NOT equal to 2a?

(a) a+a

(b) 3a-a

(c) a x 2

(d) 2a² - a

this sounds stupid i know, but i need the answer

Answer 1

2a^2-a = a(2a-1) which is obviously =/= 2a

Answer 2

The answer isC

Answer 3

(d) 2a² - a

They are not of the same terms.

Answer 4

One of the above is the answer. Its not the first one, its not the one before the last one. Its also not the one before the one before the last one. Its not the one after the first one. Its not the one after the one after the first one.