Answer: D. Romney won the most delegates in the race for 2012 nomination.
Explanation: Given the information in this graph, Romney has roughly 1500 delegates VS all the other candidates who don't even have 400 delegates. The graph does not give any information about caucuses or primaries, so A couldn't be the right answer. Paul, Gingrich, and Santorum combined is around 800, where Romney has 1500, therefore B is incorrect. And again with C, the graph does not provide any information about about primaries so therefore irrelevant, leaving D as the final answer.