Assertion : Mendel used true-breeding pea plants for his experiments.

Reason : A true-breeding line is one that has undergone continuous self-pollination

Both (A) and (R) are true but (R) is not the correct explanation of (A).

Assertion is true. Mendel used true-breeding pea plants for his experiments. True-breeding plants are those that, when self-pollinated or crossed with individuals of the same variety, consistently produce offspring with the same traits as the parent plants. These plants are genetically pure for specific traits, and their offspring will also exhibit those traits consistently.

Reason is also true. Continuous self-pollination leads to the elimination of genetic variation and the fixation of specific traits in the true-breeding lines. By repeatedly self-pollinating the plants with the desired traits, Mendel ensured the stability and uniformity of those traits in subsequent generations, making them suitable for his experiments on inheritance patterns.