MrDocherty,78,who Lives Alone,frequently Complains of Being Cold Even with a Room

Mr.Docherty,78,who lives alone,frequently complains of being cold even with a room temperature of 20°C.How can this be explained?

A) Mr.Docherty has become confused and thinks it is colder than it really is.
B) He is probably feeling lonely and wants some attention.
C) There may be a malfunction of the heat-regulating mechanism in his brain.
D) Mr.Docherty has lost subcutaneous fat and muscle tissue as he aged.