You might consider the following "small" logics in picking your choice, or explain alternative reason for your choice. I would be interested, because I am fairly certain my F2F partner made the worse choice...but who knows.
Pass - he must know what he is doing and I have four D's - go for +200
2H - Pass? You got to be kidding me, I have four diamonds this is takeout so takeout
2S - Why didn't he bid over 1S? Surely he has spades
2NT - my diamonds will stop the bleedling
3C - well, I have an honor
Other

Help

(1D) - P - (1S) - P
(2D) - P - ( P) - DBL
( P) - ? your bid