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

Question

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The Answer of 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

Let P Be a Regular Language and Q Be Context-Free