In the 1880s Harriet W. R. Strong, who urged water storage in dams, became the first ___ of flood control in the U.S.

Aextrovert
Bimposer
Cmediator
Dproponent

Verified Answer :

Proponent (meaning she tried to convince people to do it). Imposer would mean she was forcing people to build dams, and mediator would mean she was overseeing the process.