That's a good question, and between the Curt Trailer Hitch Receiver # C11484 and the Draw-Tite Trailer Hitch Receiver # 24971 that fit your 2012 Toyota Prius C, the best option is definitely the Draw-Tite # 24971.
The reason the Draw-Tite is the best option is because it has better ground clearance and bumper clearance than the Curt hitch. That means more room for the bike rack away from the vehicle and more space from the ground to the rack to prevent it from potentially hitting the ground... view full answer...
Draw-Tite trailer hitch # 24971 is a slightly modified version of 24889. It was changed slightly to accommodate additional vehicles beyond what the original 24889 hitch was able to fit. That is the only difference. view full answer...