Consider the machine M: The language recognized by M is :

• A. {w ∈ {a, b}* / every a in w is followed by ex¬actly two b’s}
• B. {w ∈ {a, b}* every a in w is followed by at least two b’}
• C. {w ∈ {a, b}* w contains the substring ‘abb’}
• D. {w ∈ {a, b}* w does not contain ‘aa’ as a substring}