The total annual vector population in Ghana, after decreasing steadily

The total annual vector population in Ghana, after decreasing steadily for the last decade, hit a low in 2004; since that time, the anopheles larval count has begun increasing steadily, prompting the vector control authorities spring into action.

A. hit a low in 2004; since that time, the anopheles larval count has begun increasing steadily, prompting

B. hit a low in 2004, but with the anopheles larval count steadily increasing, prompting

C. had hit a low in 2004; since that time, the steady increase of the anopheles larval count, which prompted

D. hit a low in 2004, and, in the case of anopheles larval count, it has increased steadily since, prompted

E. hit a low in 2004 but has since began increasing for anopheles larvae, and this prompted