Endosperm is a food laden tissue and develops from :

Primary endosperm nucleus

The correct answer is Option (2) – Primary endosperm nucleus

Explanation:

• The endosperm is a nutritive tissue that provides food to the developing embryo in angiosperms.
• It develops from the primary endosperm nucleus (PEN), which is formed when one male gamete fuses with the two polar nuclei in the central cell of the embryo sac during double fertilization.
• This results in a triploid (3n) endosperm, which later develops into the food storage tissue for the seed.

Other options:

Zygote – The zygote (2n) forms the embryo, not the endosperm.

Antipodal cells – These are located at the chalazal end of the embryo sac and do not contribute to endosperm formation.

Synergids – These are part of the egg apparatus and help in guiding the pollen tube, but they do not form the endosperm.