D(set in motion, cause to start
The answer should be A. This is because the other sentences don't need any word except for the first word in its sentence.
In the answer choice A, partners in Water partners should be capitalized because it is an organization. Therefore the sentence should be...
"<span>It was started in 2009 by actor Matt Damon and Gary White, the co-founder of Water Partners."</span>
I would say the answer is D, because when writing a summary you should probably include all of the things listed in the other options. Hope this helped!
-TTL
