Answer :
The answer is B, straining.
Explanation: straining is when you force ones body or oneself. Normally a high heart rate is a result of working too much. A high heart rate is also the cause of a heart attack, HOWEVER (C) is not correct.
Explanation: straining is when you force ones body or oneself. Normally a high heart rate is a result of working too much. A high heart rate is also the cause of a heart attack, HOWEVER (C) is not correct.