The route followed by a sperm from production to fertilization in a flowering plant is:
A. A pollen grain is produced in the anther, transported to a stigma where it produces two sperm cells that pass through a pollen tube that grows down the style to the ovary. One of the sperm cells enters the ovule and joins with the egg cell.
B. A pollen grain is produced in the pistil, which explosively ejects it into the air where it is transported to a stigma where it forms two sperm cells. One of the sperm cells passes through a pollen tube that grows down the style to the ovary, enters the ovule and joins with the egg cell.
C. A sperm cell, enclosed in a pollen grain with another sperm, is produced in the filament, transported to a stigma where it passes through a pollen tube that grows down the style to the ovary, enters the ovule and joins with the egg cell.
D. A sperm cell, enclosed in a pollen grain with another sperm, is produced in the anther, transported to the pedicel where it passes through a pollen tube that grows down the style to the ovary, enters the ovule and joins with the egg cell.
E. A sperm cell is produced in the anther, transported to a stigma where it becomes enclosed along with another sperm cell into a pollen grain that grows down the style to the ovary, enters the ovule and joins with the egg cell.
D. A sperm cell, enclosed in a pollen grain with another sperm, is produced in the anther, transported to the pedicel where it passes through a pollen tube that grows down the style to the ovary, enters the ovule and joins with the egg cell.
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