In which of the following subclasses of reptiles,the skull has a solid roof?

$A$ $Diapsid$ skull is found in which of the following groups?

When the tail is cylindrical and the ventral scales do not extend the entire width of the belly,the snake is:

Which of the following lacks a tympanum?

Which of the following is a viviparous lizard?

$Assertion (S)$: In a chameleon,permanent teeth develop after the temporary milk teeth fall out.
$Reason (R)$: Chameleon is a uricotelic animal.