Concept:In perfect competition, the market price is set by the forces of demand and supply, not by any single participant.
Explanation:A perfectly competitive market has many buyers and sellers trading identical goods.
No single buyer or seller can influence the market price.
So neither the government, the producer, nor the consumer determines the price alone.
The price is determined where market demand and market supply meet.
At this junction, the individual firm can sell any quantity it wishes at the prevailing market price.
Therefore, the correct answer refers to the interaction of demand and supply.
Answer:D. the market supply and demand junctions.