Let $X, Y, Z$ be sets and $f: X \rightarrow Y$ and $g: Y \rightarrow Z$ be functions. Then

• Correct answer
  A

  $g \circ f$ being injective implies $f$ injective.
• Correct answer
  B

  $g \circ f$ being surjective implies $g$ surjective.
• C

  $g \circ f$ being injective implies $g$ injective.
• D

  $g$ being surjective implies $g \circ f$ surjective.

Hence, the correct answer is options: 'A', 'B'.