Check My Work $(2$ rema

Suppose the parties to a case both are citizens of the same state and the law relevant to their lawsuit involves federal law. Such a case:

a$.$ must be heard in state court because there is no diversity of citizenship.

b$.$ must be heard in federal court because there is a federal question.

c$.$ may potentially be heard in either federal or state court.

d$.$ will be heard in federal court only if a third party from another state is involved.