Answer: A He knew that the coast would be clear that night.
Step-by-step explanation:
''Sorry, Wrong Number'' is a play by Lucille Fletcher about a woman who overhears a phone call between a man and his boss who were hired by a client to impending murder a helpless woman at 11:15pm who would be alone for the night.
As she narrates the details of the call to the police, she realizes that she may just be the target. Evidence points to her husband being the client because only he could have known that the woman would be alone for the night as he was on a trip and the maid had the night off.