Answer :
ANS
Mary didn't hear the phone.she Was sleeping.
( D )
Thank You !!
Answer:
D- was sleeping
Explanation:
Process of elemination-
Mary didn't hear the phone. She was (a) sleeps. (doesn't sound right) X
Mary didn't hear the phone. She was (b) slept. (no, again) X
Mary didn't hear the phone. She was (c) sleep. (nope!) X
Which leaves D. the correct answer.