Assertion : Hydrogen cannot be prepared in laboratory.
Reason : Hydrogen of high purity is obtained by electrolysing warm aqueous barium hydroxide between Nickel electrods.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are False.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "Hydrogen cannot be prepared in laboratory."
- This statement is **false**. Hydrogen can indeed be prepared in a laboratory setting through various methods, such as the reaction of zinc with dilute hydrochloric acid (HCl) or by electrolysis of water.

### Step 2: Analyze the Reason
The reason states: "Hydrogen of high purity is obtained by electrolyzing warm aqueous barium hydroxide between nickel electrodes."
- This statement is **true**. Electrolysis of warm aqueous barium hydroxide does yield hydrogen gas of high purity. This method is preferred because barium hydroxide solution conducts electricity better than plain water.

### Step 3: Conclusion
Since the assertion is false and the reason is true, we can conclude that:
- The assertion does not support the reason, and thus they are not aligned.

### Final Answer
- The assertion is false, and the reason is true. Therefore, the correct answer is that both the assertion and the reason are not true in the context of their relationship.