Answer:
d. Everyone would have been better off to stay at home.
Explanation:
Negative Externality is when the benefits of economic activities to third parties is less than the costs.
If all 10 friends use the ski, the cost to others would be greater than its benefit.
If price is raised, the demand for the ski would fall on accordance to the law of demand.
Pigovian tax is tax levied on negative externality with the goal of eliminating it.
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