Perisperm differs from endosperm is that it is :

diploid having no reserve food

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

Endosperm: In flowering plants, the endosperm is typically triploid (3n) and forms as a result of the fusion of a sperm cell with two polar nuclei during double fertilization. It usually contains reserve food materials to nourish the developing embryo.

Perisperm: The perisperm is derived from the nucellus tissue of the ovule, which is diploid (2n). It can sometimes provide nutrients to the developing seed but typically does not serve as the primary source of reserve food, unlike the endosperm. Seeds in which remnants of nucellus are seen are known as perispermic seeds. Examples of perispermic seed include black pepper and beet.

Thus, the correct answer is: diploid having no reserve food