Live hand
blinds are 25-50. One limper, SB calls. You are in the BB with

and check.
Flop comes

. SB checks, you check and limper checks.
Turn is

both blinds check, limper bets 150 and only you call.
River is

You are first to act. What do you do?
a) check/call
b) check/fold
c) put out a block bet of ~ half the pot
d) bet big looking to take it down now - ie at least pot size bet
e) other, please state
Thanks people