The correct formal way to ask "how are you?" in Spanish is "¿Cómo está?" (option A), using the formal second-person singular "usted."
So, the answer is A. Coma esta (though the correct spelling is "¿Cómo está?"). Option B ("¿Cómo estas?") is informal and used with "tú."
Therefore, only option A is appropriate for a formal context.