The correct option is: Option 2: Both Assertion (A) and reasoning (R) are correct but R is not the correct explanation of A.

Explanation:

• The Assertion states that many business firms have set up their own consumer service and grievance cells, which is generally true. Many businesses establish such cells to address consumer complaints and grievances efficiently.
• The Reasoning states that every consumer has a right to get relief in case the product or service falls short of their expectations, which is also true. Consumer rights include the right to seek redressal for faulty products or unsatisfactory services.

While both the Assertion and the Reasoning are correct, the Reasoning does not directly explain why many business firms have set up consumer service and grievance cells. The existence of consumer service and grievance cells can be attributed to various factors, including legal requirements, corporate responsibility, and competitive pressures, rather than solely to consumer rights. Therefore, the Reasoning does not provide a direct explanation for the Assertion.