Gary D Sep 23, 2009:

What about THE promotion - What about the promotion - best describes why you did not make a purchase today... I used a pause as we ask; what about the promotion? ---- and why didn't you make a purchase? Speaking naturally, I take a breath pause there, to emphasize or stress the point that I believed the promotion was the main cause of you not purchasing today.. Just being a native speaker and putting the stress in the sentence of How I would ask it.

Henry Whittlesey Schroeder Sep 23, 2009:

What aspect of XXX is certainly the right approach. It is an odd question with promotion, but certainly possible. To me it seems more likely you would say: what aspect of the offer/product/service best describes why you did not...

Andrew Mason Sep 23, 2009:

Henry, I would have no trouble interpreting the phrase as I said. It is, doubtless, a little short on grammar, but the world is not perfect.

Mark Chen (asker) Sep 23, 2009:

What is your suggestion, Henry?

Henry Whittlesey Schroeder Sep 23, 2009:

No, it is not correct, and even a correct version, like Andrew's, would be odd.