"Can You Believe It? Another Cell Phone, and This One

Multiple Choice

"Can you believe it? Another cell phone, and this one looks expensive!" the cosmetics salesperson laughed as she waved the cell phone that the customer had left behind. "Well, put it in the drawer with the others," her co-worker said. "They'll probably come back for this one." Such everyday instances of absentmindedness are usually caused by:

A) retrieval failure.
B) prospective memory failure.
C) encoding failure.
D) source confusion.