Private markets fail to account for externalities because:

• A. externalities only occur in monopolistic markets
• B. market participants do not consider the impact of their actions on third parties
• C. government regulations always eliminate externalities
• D. all costs and benefits are always internalized by buyers and sellers

Answer: (B)

Verified step by step guidance

1. Understand the concept of externalities: Externalities occur when the actions of individuals or firms have effects on third parties that are not reflected in market prices.
2. Recognize why private markets fail to account for externalities: Market participants typically consider only their own costs and benefits, ignoring the external costs or benefits imposed on others.
3. Analyze the options given: Externalities are not limited to monopolistic markets; they can occur in any market structure. Government regulations may reduce but do not always eliminate externalities. Also, not all costs and benefits are internalized by buyers and sellers in private markets.
4. Identify the correct reasoning: The failure arises because market participants do not take into account the impact of their actions on third parties, leading to market failure.
5. Summarize the key point: Private markets fail to account for externalities because the external costs or benefits are not included in the decision-making process of buyers and sellers.