Which of the following statements is false?
(b) is False. Any language is a subset of $\Sigma^*$ which is a regular set. So, if we take any non-regular language, it is a subset of a regular language.
(a) and (c) are regular as any finite language is regular.
(d) is regular as regular set is closed under intersection.
(c) Every finite subset of a regular set is regular this is false
example:a^n b^n from regular set (a+b)* is not regular