Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Flourine has smallest size amongst all halogens and is highly electronegative.
Reason R : F only forms one oxoacid HOF
In the light of the above statements, choose the most appropriate answer from the options given below :

Options

A. Both A and R are correct and R is the correct explanation of A.
B. Both A and R are correct but R is NOT the correct explanation of A.
C. A is correct but R is not correct.
D. A is not correct but R is correct

Explanation

To analyze the given statements, we will evaluate both the Assertion (A) and the Reason (R) step by step.

### Step 1: Evaluate the Assertion (A)
**Assertion A:** "Fluorine has the smallest size amongst all halogens and is highly electronegative."

- **Size of Fluorine:** Fluorine is indeed the smallest halogen. This is due to its position in the periodic table; it is located in the second period, and as you move down the group, the atomic size increases due to the addition of electron shells.

- **Electronegativity of Fluorine:** Fluorine is the most electronegative element in the periodic table, with an electronegativity value of 4.0 on the Pauling scale. This high electronegativity is a result of its small size and the effective nuclear charge experienced by its valence electrons.

**Conclusion for Assertion A:** The assertion is true.

### Step 2: Evaluate the Reason (R)
**Reason R:** "F only forms one oxoacid HOF."

- **Oxoacids of Fluorine:** The statement claims that fluorine only forms one oxoacid, which is hypofluorous acid (HOF). This is correct. Fluorine, due to its high electronegativity and small size, does not have the ability to form multiple oxoacids like other halogens (e.g., chlorine can form HClO, HClO2, HClO3, and HClO4).

- **Explanation:** The reason provided explains why fluorine forms only one oxoacid, which is due to its high electronegativity and the inability to stabilize higher oxidation states.

**Conclusion for Reason R:** The reason is also true and correctly explains the assertion.

### Final Conclusion
Both the Assertion (A) and Reason (R) are true, and the reason correctly explains the assertion. Therefore, the most appropriate answer is that both statements are true, and the reason is a correct explanation of the assertion.