Make an order of magnitude estimate of the following quantity. Explain the assumption used in your estimation. The number of times the average person's heart beats in a day Choose the correct answer below. O A. 86,400; assuming an average person's heart beats once a second O B. 8640; assuming an average person's heart beats once every 10 seconds O C. 432,000; assuming an average person's heart beats 5 times a second O D. 1440; assuming an average person's heart beats once a minute