单选题 An investor buys two calls and one put on ABC stock, all with a strike price of $45. The calls cost $5 each, and the put costs $4. If the investor closes the position when ABC is priced at $55, the investor"s per share gain or loss is :

A、 $4 loss.
B、 $6 gain.
C、 $10 gain.

【正确答案】 B

【答案解析】The combined cost of the two options is (2 × $5 ) + $4 = $14.
At expiration, the put is worth Max [0, 45 -55] = $0.
Each of the two calls is worth Max[0, S -X ] = $10.
Thus, the per share gain/loss is: - $14+ $0+(2× $10) = $6.