Which one of the following indicates the correct order of atomic size?
(1). `C gt F gt Ne" "(2) Be lt C lt F lt Ne`
`(3). Be gt C gt F" "(4) F gt Ne gt Be gt C`

Explanation

To determine the correct order of atomic size among the given options, we need to consider the periodic trends in atomic size. Atomic size generally decreases across a period from left to right due to increasing nuclear charge, which pulls the electrons closer to the nucleus. Conversely, atomic size increases down a group due to the addition of electron shells.

Let's analyze the options step by step:

### Step 1: Understand the Elements and Their Positions
- **Carbon (C)**: Atomic number 6, located in Group 14 (4A), Period 2.
- **Fluorine (F)**: Atomic number 9, located in Group 17 (7A), Period 2.
- **Neon (Ne)**: Atomic number 10, located in Group 18 (Noble gases), Period 2.
- **Beryllium (Be)**: Atomic number 4, located in Group 2 (2A), Period 2.

### Step 2: Compare Atomic Sizes Across Period 2
- All the elements listed (C, F, Ne, Be) are in Period 2.
- As we move from left to right across Period 2 (from Be to Ne), the atomic size decreases due to the increase in nuclear charge without a corresponding increase in shielding effect.

### Step 3: Determine the Trend
- **Beryllium (Be)** will have the largest atomic size because it is the furthest left in the period.
- **Carbon (C)** will be smaller than Beryllium but larger than Fluorine and Neon.
- **Fluorine (F)** will be smaller than Carbon due to its higher nuclear charge.
- **Neon (Ne)** will have the smallest atomic size among these elements due to its complete electron shell, which leads to a greater effective nuclear charge.

### Step 4: Establish the Correct Order of Atomic Size
Based on the analysis:
- The correct order of atomic size from largest to smallest is: **Be > C > F > Ne**.

### Step 5: Evaluate the Given Options
1. **C > F > Ne**: Incorrect, as Ne is smaller than both C and F.
2. **Be < C < F < Ne**: Incorrect, as Be is larger than C, F, and Ne.
3. **Be > C > F**: Correct, but does not include Ne.
4. **F > Ne > Be > C**: Incorrect, as it misplaces the order entirely.

### Conclusion
The correct order of atomic size is **Be > C > F > Ne**. However, since this specific order is not listed in the options, we can conclude that option (3) **Be > C > F** is the closest correct trend, but it does not include Neon.