The support for a central argument is a Select one:
major claim
justification
rebuttal
subclaim

Option D, sub-claim, is the right answer.

Explanation:

A sub-claim is also known as a supporting statement. It is used to support the main claim or the central argument of our work. The central argument of the paper can be wrapped in a single sentence whereas the sub-claims can be many other statements in support of the main argument. The sub-claims are specific and include reasons, claims, evidence etc. to explain why the main argument is accurate.

the correct answer would be d.