The correct answer is C. flower.
Pollen grains are produced in the anthers of the flower. The anthers are located at the top of the stamen, which is one of the male reproductive organs of the flower. The anthers are made up of four pollen sacs, which contain the pollen grains. The pollen grains are released from the anthers when they are mature and are carried by the wind or by insects to the stigma of the female reproductive organ of the flower.
The roots of a plant are used to absorb water and minerals from the soil. The leaves of a plant are used to photosynthesize, which is the process by which plants use sunlight to create food. The stem of a plant supports the leaves and flowers and transports water and nutrients from the roots to the leaves.
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