Assertion (A): Hydrogen shows a dual nature.

Reason (R): Hydrogen resembles both the alkali metals of group 1A and the halogens of group VIIA.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion (A): Both dilute sulphuric acid and dilute hydrochloric acid displace hydrogen when they react with metals above hydrogen in the activity series.

Reason (R): The more reactive element displaces the less reactive element from its salt solution.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion (A): Zinc is preferred for the laboratory preparation of hydrogen.

Reason (R): Zinc is unique in nature and does not contain any impurity.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Assertion (A): Reduction is defined as the process of removal of oxygen from a substance or the addition of hydrogen to a substance.

Reason (R): Hydrogen is a reducing as well as an oxidising agent.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.