Pass? to pessimistic and is out, 3H? I would never overcall a 4-card suit at 3-level. 3N? It has to be natural and to play. Unless I am crazy, I would never bid NT with stiff (and small) diamond. 5C? I wouldn't do that before consulting with my pd. That leaves dbl and 4C. Over my dbl, if pd bids 3S, I will "correct" to 4C, hopefully pd would not take it as double-and-bid hand; If my pd bid 4S, I would have to pass. I will also pass my pd's 3NT. 4C is the least evil bid.