The correct answer is option 4, "Anther." Pollens are produced in the anther, which is the male reproductive organ of a flower. The anther is a part of the stamen, which is one of the essential parts of a flower.

The anther contains tiny structures called microsporangia, within which pollen grains are produced. These pollen grains contain the male gametes of the flower, which are involved in the process of fertilization.

Option 1, "Corolla," is incorrect as the corolla refers to the collection of petals in a flower that collectively form the innermost whorl of nonreproductive floral parts.

Option 2, "Style," is also incorrect as the style is a long, slender structure that connects the stigma to the ovary. It plays a role in pollen tube formation and guiding the pollen grains towards the ovary during fertilization.

Option 3, "Stigma," is incorrect as well because the stigma is the sticky or feathery surface at the top of the style that receives the pollen grains and facilitates their germination.

Therefore, the correct answer is option 4, "Anther," as it is the specific part of the flower where pollens are produced.