Your last patient of the day is Mr. Oganesyan, a 67 year old…

Your last patient of the day is Mr. Oganesyan, a 67 year old man with a history of high blood pressure.  While talking to Mr. Oganesyan, you notice that the left corner (angle) of his mouth does not elevate when Mr. Oganesyan smiles.  Which of the following muscles normally elevates the angle of the mouth when a person smiles?