The correct option is C Mangifera indica Linn.
Providing a scientific name to the organism with two components is called binomial nomenclature. This was first practiced by Linnaeus and is followed by biologists all over the world.
The first component in the scientific name is genus, while the second component is specific epithet.
Genus starts with a capital letter while the specific epithet starts with a small letter. The scientific names are printed in italics. If handwritten, they are underlined separately.
Hence, the correctly written scientific name of mango is Mangifera indica. Mangifera denotes genus and indica denotes specific epithet.
The name of the author appears after the specific epithet, i.e., at the end of the biological name and is written in an abbreviated form. For example: Mangifera indica Linn. It indicates that mango was first described by Linnaeus.
Hence, Mangifera indica Linn. is the scientific name of Mango as per rules of binomial nomenclature given by Carolus Linnaeus.