Which of the following characteristics are $NOT$ common to both Aves (birds) and Mammalia (mammals)?
$I$ - Homeothermic (warm-blooded) animals.
$II$ - Respire through lungs.
$III$ - Possess a four-chambered heart.
$IV$ - Dioecious (sexes are separate).
$V$ - Possess hair on the skin.
$VI$ - Show internal fertilization.
$VII$ - Possess teeth.

• A
  $V, VII$
• B
  $I, II, III, IV, VI$
• C
  $I, III, V, VII$
• D
  $II, IV, VI$