Consider the following types of languages: L1 : Regular,

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Consider the following types of languages: L₁ : Regular, L₂ : Context-free, L₃ : Recursive, L₄ : Recursively enumerable.
Which of the following is/are TRUE?
I. L₃ ∪ L₄ is recursively enumerable
II. L₂ ∪ L₃ is recursive
III. L₁* ∩ L₂ is context-free
IV. L₁ ∪ L₂ is context-free

1. I only
2. I and III only
3. I and IV only
4. I, II and III only

Correct Option: D

Statement (IV): L₂ may or may not be context free because CFL are not closed under complementation. So it is not true.