Answer: option A is the correct answer.
Step-by-step explanation:
The cost of oranges in a grocery store is directly proportional to the number of oranges purchased. Jerri paid $2.52 for 6 oranges.
 If p represents the cost, in dollars,and n represents the number of oranges purchased, then introducing a proportionality constant, k, the equation becomes
p = kn 
2.52 = k × 6
k = 2.52/6 = 0.42
Therefore, the equation representing the relationship is 
p = 0.42n