The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
A tautonym is a scientific name of a species in which both parts of the name have the same spelling. According to binomial nomenclature, each plant has been given a botanical name which has two parts. First is a generic part which has an initial capital letter and the second part, called species, is written in small letters. The scientific name Malus malus is illegitimate because the genus and species name both spell the same.