Q.) The table given below shows the reaction
of a few elements with acids and bases to
evolve Hydrogen gas.

Which of these elements form amphoteric oxides ?
(a) A and D
(b) B and D
(c) A and C
(d) B and D
Ans. (b) B and D
Explanation: Amphoteric oxides are the
metal oxides that show both acidic and basic
nature.