The sky is clear today.

Correct — B, opaque. Here 'clear' means transparent and easy to see through, and its opposite is 'opaque', which means not able to be seen through, so it is the correct antonym.

Why the others are wrong

• (a)
  bright — 'Bright' means full of light; it is not the opposite of 'clear'.
• (c)
  cloudless — 'Cloudless' means free of clouds — a synonym of a clear sky, not its opposite.
• (d)
  blue — 'Blue' names a colour; it has no opposite relationship with 'clear'.

An antonym item — 'clear' means transparent, so its opposite is 'opaque' (not see-through); 'cloudless' is a near-synonym placed as a trap.

No directly related past PYQ was found.

• practice — not a real PYQ

  Select the word opposite in meaning to 'transparent'.

  • (a)clear
  • (b)opaque
  • (c)glassy
  • (d)open
  Answer(b) opaque — 'transparent' lets light through; 'opaque' does not, so it is the opposite.
• practice — not a real PYQ

  Select the word opposite in meaning to 'lucid'.

  • (a)clear
  • (b)obscure
  • (c)plain
  • (d)simple
  Answer(b) obscure — 'lucid' means clear and easy to understand; 'obscure' means unclear, so it is the opposite.