Assertion: Arthritis or inflammation of a joint makes the join painful.

Reason: Some toxic substances are formed in the muscles.

a. Both the assertion and the reason are true and the reason is a correct explanation of the assertion
b. Both the assertion and reason are true but the reason is not a correct explanation of the assertion.
c. The assertion is true but the reason is false.
d. Both the assertion and reason are false.

Dear student, Arthritis is the condition which results in painful joints. This is because the cartilage present in between the bones gets calcified and damaged resulting in the swelling and inflammation of the joints due to friction between the long bones. This leads to deposition of uric acid between the joints which is called as gout. Uric acid is the metabolized product of purines and amino acids. This results in pain and decreased mobility. Thus, the correct answer is option A. Thanks and regards.