The outer skin of a fruit is called
(A)Mesocarp
(B)Endocarp
(C)Epicarp
(D)Seed

Hint: In fruits, the pericarp is made up of three layers. Another name for the outer skin of a fruit is the exocarp and even it is also known as flavedo in the case of the citrus fruits.

Complete answer:
 The outer skin of a fruit is called Epicarp. In fruits, the pericarp is usually made from three distinct layers: the epicarp (also referred to as exocarp), which is that the outermost layer; the mesocarp, which is that the middle layer; and therefore the endocarp, which is that the inner layer surrounding the ovary or the seeds in citrus, the epicarp and mesocarp structure the peel. In dry fruits, the layers of the pericarp aren't distinguishable.

Additional Information: Other than epicarp, the 2 other layers are :
Mesocarp-
The mesocarp is the fleshy middle layer of the pericarp of a fruit; it's found between the epicarp and therefore the endocarp. it's usually a part of the fruit that's eaten. for instance, the mesocarp makes up most of the edible part of a peach, and a substantial part of a tomato. "Mesocarp" can also ask any fruit that's fleshy throughout.
In a hesperidium, as is found in citrus, the mesocarp is additionally mentioned as albedo or pith. it's the inner part of the peel and is usually removed before eating.
Endocarp
Endocarp is the botanical term for the within the layer of the pericarp (or fruit), which directly surrounds the seeds. it's going to be membranous as in citrus where it's the sole part consumed, or thick and hard as within the stone fruits of the Rosaceae like peaches, cherries, plums, and apricots.
In nuts, the endocarp which is present is the stony layer that surrounds the kernel of pecans, walnuts, etc., which is removed before consumption.
In citrus fruits, the endocarp is separated into the sections, which are called the segments. These segments are crammed with juice vesicles, which contain the juice of the fruit.
So, the correct answer is ‘Epicarp’.

Note: The grains of grasses are single-seed simple fruits wherein the pericarp (ovary wall) and testa are fused into one layer. This sort of fruit is called a caryopsis. Examples include cereal grains, like wheat, barley, and rice.