The correct option is A Basidiocarp
The fungal body in basidiomycetes is made up of a number of white thread-like structures called hyphae. A bunch of hyphae are called mycelia.
Basidiospores are the spores formed in the basidia (spore-bearing structure) during reproduction and the basidia are arranged in fruiting bodies called basidiocarps. The basidiocarp forms the edible part of the mushroom. Agaricus bisporus (button mushrooms) is the most common type of edible mushroom.