Option 1 states that both the assertion (A) and the reason (R) are true, and that the reason is the correct explanation of the assertion. However, this is not accurate because the assertion is false. Option 2 also states that both A and R are true, but it acknowledges that R is not the correct explanation of A. This is the correct answer.

The assertion states that all flying animals belong to the class of Aves. However, this is incorrect because not all flying animals belong to the class Aves. Bats, for example, are mammals, not birds.

The reason given states that all flying animals have wings. While this is generally true - most flying animals do have wings - it is too broad of a statement to be a correct explanation for the assertion. There are exceptions to this, such as flying squirrels, which use skin flaps to glide through the air rather than wings.

Therefore, option 2 is the correct answer as it correctly identifies that both the assertion and the reason are true, but the reason does not explain the assertion accurately.