Explain the answers please

How do external costs prevent a competitive market from allocating resources efficiently? External costs prevent a competitive market from allocating resources efficiently because firms consider_ when they make their production decisions. Quantity (tons per week) Marginal cost Marginal Marginal social cost social benefit (dollars per ton) 60 60 240 80 O A. private and external costs B. only the costs that they bear O C. external costs and external benefits OD. the costs that they bear and the benefits that consumers receive 100 a AWN 105 150 195 240 180 150 120 120 140 90 The table describes the market for pesticide, which is a market with a negative externality. When a factory produces pesticide, it dumps waste into a lake. A trout farm uses the lake. If the market is unregulated, what is the quantity of pesticide produced? If the market is unregulated, the quantity of pesticide produced is 4 tons a week. This outcome is ___ _because marginal social cost__marginal social benefit. O A. inefficient; is less than B. inefficient; exceeds; OC. efficient; equals; OD. efficient; plus marginal external cost equals