Which of the Following Scenarios Is an Example of Separation

Which of the following scenarios is an example of separation anxiety?

A) Tommy hits his 10-month-old brother, John. Now, whenever John sees Tommy in the room, John begins to cry.
B) Kerry has been in day care since she was three months old. She has always seemed happy there. But now she is 10 months old and has started to cry every morning as soon as she sees the door to the day care center.
C) Andrea is laying in her crib, about to fall asleep. A car backfires outside her window and Andrea begins to cry.
D) Adrian's mother walks into a crowded store, holding Adrian in her arms. Adrian looks at the strangers in the room and pushes away from his mother's arms.