I decided to make a standard raise to $18 and the BB reraises to $54. We both are consistently making c-bets after raising/reraising. I call with JhJs. BB makes c-bet of $75 on a flop of: QdJc7s. I reraise to $200 and he flat calls. The BB checks a turn of: 7d. I bet $200 on the turn and he flat calls. The river is: 5h. He checks the river and you bet $300 and he ends up instantly pushing over the top of your bet. What is he most likely holding'?

A. KK
B. QQ
C. 77
D. 55