I believe the answer to your question will be atrioventricular but don't cross out pulmonary it could possibly be the answer.
Answer:
B. Negative Reinforcement
Explanation:
They are reinforcing her behavior of being bothersome by inherently rewarding her instead of letting her know they are busy and teaching her patience
It is true that unlike erythrocytes, leukocytes have a nucleus and do not contain hemoglobin.
Coping is the effort to control, reduce, or tolerate threats that lead to stress.