The compound(s) which react(s) with $\mathrm{NH}_{3}$ to give boron nitride (BN) is(are)

The correct option(s) related to the extraction of iron from its ore in the blast furnace operating in the temperature range $900-1500 \mathrm{~K}$ is(are)

Considering the following reaction sequence, the correct statement(s) is(are)

Among the following, the correct statement(s) about polymers is(are)