Part(s) of a flower which attracts insects for pollination is (are)

In a flower, the petals are typically brightly colored, large, and sometimes scented. Their primary evolutionary function is to attract insects, birds, and other animal pollinators to facilitate pollination.

• Sepals (Option A and D) are green, leaf-like structures that protect the flower in its bud stage; they do not play a primary role in attracting insects.
• Anther and Stigma (Option B) are the male and female reproductive organs respectively, involved directly in producing pollen and receiving it, rather than attracting insects.

Thus, petals only are specialized for attracting insects.