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Reproduction in flowering plants or angiosperms is a result of fertilization specifically double fertilisation.

Double fertilization is unique to flowering plants. Double fertilization takes place when one sperm cell fuses with the egg cell to form the zygote and another sperm cell fuses with the secondary nucleus to form the endosperm.

• The fruits are a result of the ovarian growth which starts to enlarge and become the fruit after fertilization takes place.
• Endosperm is a result of the fusion between the second sperm cell and the secondary nucleus. The endosperm is made up of three haploid nuclei fused together. The cotyledons in seeds develop from the endosperm.
• The zygote formed after the fusion of the sperm cell and the egg cell undergoes multiple cell divisions to form the embryo.

The events that take place after fertilization are:

• Embryo starts dividing mitotically, resulting in the formation of a multicellular embryo. The endosperm nucleus splits and generate a mass of endosperm cells that feeds the growing embryo.
• The dividing embryo ultimately develops into a mature embryo in the ovule, that develop into seed.
• Ovary starts to grow and enlarge that goes on to become the fruit within which the seed develops.
• As the fruit and seed start to form the petals and sepals come off.

As a result, Option is the correct response (b)