Which test is used as a basis of qualification for the Child Tax Credit and not for the Earned Income Tax Credit?

The correct answer is based on the "Support" test, which is specifically pertinent to the qualifications for the Child Tax Credit. For the Child Tax Credit, a qualifying child must not only meet age and relationship requirements but also the criterion that the taxpayer provides more than half of the child's support during the year. This is crucial because it ensures that the taxpayer is significantly involved in the child's well-being and support, which aligns with the intent of the Child Tax Credit to benefit families who are actively caring for children.

In contrast, the Earned Income Tax Credit focuses primarily on income and family composition, rather than the level of support provided for a child. While the support aspect can play a role in determining who qualifies for EITC based on dependents, it is not a direct qualifier in the same way it is for the Child Tax Credit. Therefore, it is the support test that distinctly applies to the qualifications for the Child Tax Credit, making it the key differentiator in this context.