Dave's ESL Cafe's Student Discussion Forums

[www0935]

The following is my question:

Surprisingly, most of the workers chose the boxes that were painted white�that is, the heavy ones. According to the researchers, this is ______ light colors tend to make objects �look� lighter in weight.
(A) why (B) which (C) because (D) the reason

Which one is the correct answer? Is there any difference between "why" and "because" in this sentence?

Thanks for your help.

[pugachevV]

No, you have to use because here, because it explains the reason why workers picked the heavy boxes. (light colours make things look lighter).

You can't use this is why because the reason has not yet been given.

If you wanted to use why you would say, (for instance) "Light colours make things look lighter, this is why the workers chose the heavy boxes."