Butterfly spread payoffs can be created in the following way (European options, all same maturity) a) Buy 1 K=90 call, Sell 3 K=100 calls, Buy 2 K=120 calls b) Buy 1 K=90 call, Sell 3 K=100 calls, Buy 2 K=110 calls c) Sell K=100 straddle, Buy 1 K=90 call, Buy 1 K=110 put d) Sell K=100 straddle, Buy 1 K=90 put, Sell 1 K=110 call e) c. and d. are correct