Why is it mandatory to always start the species name with lowercase letters when writing a scientific name?

Correct answer: It is a strict and mandatory rule of international nomenclature codes

The correct answer is A. In a binomial scientific name, the first word is the genus and begins with a capital letter, while the second word is the specific epithet and begins with a lowercase letter. This capitalization convention is prescribed by international nomenclature codes so that scientific names are written uniformly worldwide. It is not a matter of writing speed or personal preference. Option B is wrong because lowercase writing is not selected to save time. Option C is an unsupported personal explanation and is not the basis of the rule. Option D is wrong because a clear convention does exist. For example, in Mangifera indica, Mangifera begins with a capital M, whereas indica begins with a lowercase i. Strictly speaking, the complete species name is the two-word combination, not the second word alone. Memory cue: Genus gets a capital, specific epithet gets a small letter.