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.