Correct Answer :
B. anther
Pollen grains are produced within the anther of stamen. Anther is the pollen-bearing part at the upper end of the stamen of a flower. Most anthers occur at the tip of a slender, stem-like filament and have two lobes. Each lobe contains two pollen sacs. When pollen matures in the pollen sacs, the lobes of the anthers burst open in the process known as dehiscence to release the pollen.