John Receives a Marginal Benefit of $80 from One Missile

John receives a marginal benefit of $80 from one missile. Nick receives a marginal benefit of $50 from one missile. Christina receives a marginal benefit of $65 from one missile. John, Nick, and Christina are the only people in the economy. What is the economy's marginal social benefit from one missile?

A) $50
B) $65
C) $80
D) $195