You Take Mrs

You take Mrs.Main's temperature at 7:00 am.; it reads 97.8° F (36.6° C) .At 3:00 p.m.,you take her temperature again; it reads 99° F (37.2° C) .How do you account for the difference?

A) During sleep,body metabolism slows down.
B) Mrs.Main normally runs a low body temperature.
C) During sleep,muscle activity increases.
D) Women normally run a higher body temperature than men.