Following elements are present in the second period of the periodic table from left to right.
Li, Be, B, C, N, O, F, Ne
Few statements are given about these elements:
(i) O and F exist as monatomic gases.
(ii) Li is the lightest element in the period.
(iii) B is a metalloid while C is a metal.
(iv) Li and F react to form a compound LiF.
The correct statements are A.

Options

A. (i) and (iii) only
B. (ii) and (iv) only
C. (ii) and (iii) only
D. (i) and (iv) only.

Answer

To determine the correct statements about the elements in the second period of the periodic table, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement (i): O and F exist as monatomic gases.**
- **Analysis**: Oxygen (O) exists as O₂ (diatomic) and fluorine (F) exists as F₂ (diatomic) in their gaseous forms. Therefore, this statement is **false**.

2. **Statement (ii): Li is the lightest element in the period.**
- **Analysis**: Lithium (Li) has an atomic mass of approximately 7, while beryllium (Be) has an atomic mass of approximately 9. Since lithium has a lower atomic mass than beryllium, this statement is **true**.

3. **Statement (iii): B is a metalloid while C is a metal.**
- **Analysis**: Boron (B) is indeed classified as a metalloid, but carbon (C) is a non-metal, not a metal. Therefore, this statement is **false**.

4. **Statement (iv): Li and F react to form a compound LiF.**
- **Analysis**: Lithium (Li) reacts with fluorine (F) to form lithium fluoride (LiF), which is a stable ionic compound. Therefore, this statement is **true**.

### Conclusion:
The correct statements are:
- Statement (ii): Li is the lightest element in the period.
- Statement (iv): Li and F react to form a compound LiF.

Thus, the correct answer is **A. Statements (ii) and (iv) are correct**.