Morphology of Flowering Plants

Mango is a drupe: a fleshy, one-seeded fruit developing from a monocarpellary superior ovary.
Its pericarp has a thin outer epicarp (skin), a fleshy, juicy mesocarp, and a hard, stony endocarp around the seed.
The fleshy mesocarp is the part that is eaten.
So the edible part of mango is the mesocarp.

Geocarpy is the development of fruits underground.
In peanut (groundnut, Arachis hypogaea), after fertilisation the stalk of the ovary (gynophore) elongates, bends down and pushes the young ovary into the soil, where the pod develops and ripens.
Potato is a stem tuber and onion and garlic are bulbs; these are underground stems, not fruits.
So the geocarpic fruit is peanut.

Bladderwort is Utricularia, an aquatic insectivorous plant with bladders that trap small animals.
Sundew is Drosera, whose leaves bear sticky glandular tentacles that trap insects.
Venus flytrap is Dionaea, whose two-lobed leaves snap shut on insects.
(Nepenthes is the pitcher plant; Vanda is an epiphytic orchid; Trapa is the water chestnut.)
So the correct match is Utricularia, Drosera, Dionaea.