(D) Click-through rate
(E) All of the above
The bid strategy of your Ads campaign depends on all of the above keyword metrics like Impressions, Clicks, Position, Click-through Rate. If your Ad is getting a lot of impressions but less clicks then you need to increase your bid. If your Ad is getting less clicks then, it means your ad is positioned at the bottom so you need to increase the bid. Similarly, if the Ad position is low then increasing the bid can bring your Ad to a higher position. Lastly, if your ad has a low Click-Through Rate(CTR) then chances are it is poorly positioned so increasing the keyword bid can increase your position and improve your CTR.
This question is a part of the Microsoft Advertising Certified Professional exam. You can find all the answers with full explanation for this exam in our Microsoft Advertising Certified Professional Exam Answers page.