Which revision best corrects the errors in the given sentence?
A firm handshake like a friendly smile, a pleasant attitude, and good manners is a valuable asset in life.
A.
A firm handshake—like a friendly smile, a pleasant attitude, and good manners—is a valuable asset in life.
B.
A firm handshake: like a friendly smile; a pleasant attitude; and good manners, is a valuable asset in life.
C.
A firm handshake, like a friendly smile, a pleasant attitude, and good manners—is a valuable asset in life.