The policy applies in some states, where there
is a federal law and a provincial law that are each valid and enforceable.
A.
is a federal law and a provincial law that are each valid and enforceable -> FLIP the related part: A federal law and a provincial law
are there. By flipping, we can see that the compound subject '
a federal law and a provincial law' takes a plural verb '
are'.
B. are a federal law and a provincial law,
each of which
are valid and enforceable ->The indefinite pronoun
each is considered a singular pronoun and requires a singular verb form.
C. a federal law and a provincial law both of which are valid and enforceable -> Try to replace the underlined part with this fragment. A connecting verb between
there and
this fragmentis missing.
D. are a federal law and a provincial law that are valid
or enforceable -> Use of
or changes the meaning of the sentence.
E. are a federal law and a provincial law that are each valid and enforceable. Contrast this with A. It uses the correct verb
there are. The second verb form that might be confusing
that are is also correctly used. Hence, This is the correct answer.
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