Given this protocol:

Alice to Bob: $"$I$\text{'}$m Alice"

Bob to Alice: $"[$R$]$Bob$"$

Alice to Bob: $"[$R$]$Alice$"$

Where $[..]$ is the signature.

Is mutual authentication ensured?

Group of answer choices

Yes, Alice and Bob are both authenticated

No$,$ Alice is not Authenticated

No$,$ neither of the two is authenticated

No$,$ Bob is not authenticated