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Q. |
## Let P be a regular language and Q be context-free language such that Q ∈ P. (For example, let P be the language represented by the regular expression p*q* and Q be {pnqn n∈ N}). Then which of the following is ALWAYS regular? |

A. | P ∩ Q |

B. | P – Q |

C. | ∑* – P |

D. | ∑* – Q |

Answer» C. ∑* – P |

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