Sheila Has Difficulty Paying Attention in Class

Multiple Choice

Sheila has difficulty paying attention in class.To improve her behaviour,her teacher taped a form to Sheila's desk and gave her a tape player with an ear-phone that provided a random-tone prompt.Each time she heard the tone,Sheila asked herself "Am I paying attention?",then placed a check mark in the "yes" or "no" column on the sheet.This is an example of

A) self-instruction.
B) self-monitoring.
C) self-control.
D) self-reinforcement.