Choose the incorrect sentence.

• A
  Many tribes live in the high altitude of Himalayas; they normally have a higher red blood cell count than people living in the plains.
• B
  At high altitude,we must have experienced what is called altitude sickness.
• C
  Archaebacteria live in hot springs where the temperature exceeds $100^{\circ}C$.
• D
  Mammals from colder climates generally have shorter ears and limbs. This is called Allen's rule.