(A) Ether behaves as bases in the presence of mineral acids.
(R ) Due to the presence of lone pair of electrons on oxygen.

Options

A. if both assertion and reason are true and reason is thr correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reson are false.

Explanation

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Ether behaves as bases in the presence of mineral acids."
- Ethers are compounds with the general structure R-O-R', where R and R' are alkyl or aryl groups.

2. **Understanding the Reason**:
- The reason states that this behavior is "due to the presence of lone pairs of electrons on oxygen."
- In ethers, the oxygen atom has two lone pairs of electrons.

3. **Defining a Base**:
- A base, according to Lewis theory, is a substance that can donate a pair of electrons.
- Since ethers contain oxygen with lone pairs, they can act as Lewis bases.

4. **Reaction with Mineral Acids**:
- When ethers encounter mineral acids (like HCl, H2SO4, etc.), the oxygen atom can donate one of its lone pairs to a proton (H+).
- This results in the formation of an oxonium ion (R-OH2+), which confirms that ethers can act as bases.

5. **Conclusion**:
- Both the assertion and the reason are correct.
- The reason provided accurately explains why ethers behave as bases in the presence of mineral acids.

### Final Answer:
Both the assertion and reason are true, and the reason is a correct explanation of the assertion.

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