Perisperm differs from endosperm is that it is :

The correct answer is Option (4) → diploid having no reserve food

Note: Option (4) is the most appropriate answer because diploid is the real difference between perisperm and endosperm. Its words ‘having no reserve food’ are loose: the perisperm of black pepper and beet does store food.

The endosperm grows from the primary endosperm nucleus, formed when two polar nuclei fuse with a male gamete (triple fusion), so it is triploid (3n). The perisperm is the left-over nucellus, a tissue of the parent ovule, so it is diploid (2n).

Option (1) haploid having reserve food — Incorrect. The nucellus belongs to the diploid parent plant. The only haploid cells in the ovule are those of the embryo sac.

Option (2) polyploid having reserve food — Incorrect. Of the two tissues, it is the endosperm that is polyploid (triploid), not the perisperm.

Option (3) triploid having no reserve food — Incorrect. Triploid describes the endosperm, which is the main food store of the seed.

Option (4) diploid having no reserve food — Correct. The perisperm is diploid, because it comes from the nucellus and not from fertilisation.

NCERT Extract:
Seed – “… Mature seeds may be non-albuminous or ex-albuminous. Nonalbuminous seeds have no residual endosperm as it is completely consumed during embryo development (e.g., pea, groundnut). Albuminous seeds retain a part of endosperm as it is not completely used up during embryo development (e.g., wheat, maize, barley, castor). Occasionally, in some seeds such as black pepper and beet, remnants of nucellus are also persistent. This residual, persistent nucellus is the perisperm.”