Arrange the following elements in order of their number of neutrons, beginning from less to more:

(A) Nitrogen
(B) Silicon
(C) Beryllium
(D) Fluorine

Choose the correct answer from the options given below:

(C), (A), (D), (B)

The correct answer is Option (4) → (C), (A), (D), (B)

To determine the correct order, we need to calculate the number of neutrons for the most common isotope of each element. The number of neutrons is found using the formula:

$\text{Number of Neutrons} = \text{Mass Number} (A) - \text{Atomic Number} (Z)$

1. Calculating Neutrons for Each Element

(A) Nitrogen: The atomic number ($Z$) is 7 and the most common mass number ($A$) is 14.

$\text{Neutrons} = 14 - 7 = \mathbf{7}$

(B) Silicon: The atomic number ($Z$) is 14 and the most common mass number ($A$) is 28.

$\text{Neutrons} = 28 - 14 = \mathbf{14}$

(C) Beryllium: The atomic number ($Z$) is 4 and the most common mass number ($A$) is 9.

$\text{Neutrons} = 9 - 4 = \mathbf{5}$

(D) Fluorine: The atomic number ($Z$) is 9 and the most common mass number ($A$) is 19.

$\text{Neutrons} = 19 - 9 = \mathbf{10}$

2. Arranging in Increasing Order (Less to More)

Comparing the results:

1. Beryllium (5) — (C)
2. Nitrogen (7) — (A)
3. Fluorine (10) — (D)
4. Silicon (14) — (B)

The sequence is (C), (A), (D), (B).