48. In which of the following sentences is the punctuation correct?
(A) If things go wrong, it must be a personal, human error, the result of fingering, tampering, a button getting stuck, someone hitting the wrong key.
(B) If things go wrong it must be a personal, human error, the result of fingering, tampering, a button getting stuck, someone hitting the wrong key.
(C) If things go wrong: it must be a personal, human error, the result of fingering, tampering, a button getting stuck, someone hitting the wrong key.
(D) If things go wrong, it must be a personal, human error, the result of fingering, tampering, a button getting stuck someone hitting the wrong key.