Read the given passage and fill in the blanks by selecting an appropriate option.
Atomic numbers of elements P, Q, R and S are 3, 10, 12 and 20 respectively. Elements `ul((i))` belong to the same period while elements `ul((ii))` belong to the same group. For cation formation, `ul((iii))` loses electron from L-shell while `ul ((iv))` loses electrons from N-shell.

Options

A. `{:("(i)","(ii)","(iii)","(iv)"),("Q,R","P,S","P","S"):}`
B. `{:("(i)","(ii)","(iii)","(iv)"),("P,Q","R,S","P","S"):}`
C. `{:("(i)","(ii)","(iii)","(iv)"),("R,S","Q,P","R","S"):}`
D. `{:("(i)","(ii)","(iii)","(iv)"),("P,R","Q,S","P","S"):}`

Answer

To solve the question, we need to analyze the atomic numbers and electronic configurations of the elements P, Q, R, and S, which correspond to the following:

- Element P: Atomic number 3 (Lithium, Li)
- Element Q: Atomic number 10 (Neon, Ne)
- Element R: Atomic number 12 (Magnesium, Mg)
- Element S: Atomic number 20 (Calcium, Ca)

Now, let's fill in the blanks step by step.

### Step 1: Identify elements in the same period
- **P (Li)**: 1s² 2s¹ (2nd period)
- **Q (Ne)**: 1s² 2s² 2p⁶ (2nd period)
- **R (Mg)**: 1s² 2s² 2p⁶ 3s² (3rd period)
- **S (Ca)**: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² (4th period)

**Conclusion for (i)**: Elements P and Q belong to the same period (2nd period).

### Step 2: Identify elements in the same group
- **Group of P (Li)**: Group 1 (Alkali metals)
- **Group of Q (Ne)**: Group 18 (Noble gases)
- **Group of R (Mg)**: Group 2 (Alkaline earth metals)
- **Group of S (Ca)**: Group 2 (Alkaline earth metals)

**Conclusion for (ii)**: Elements R and S belong to the same group (Group 2).

### Step 3: Determine which element loses an electron from the L-shell for cation formation
- **P (Li)**: Has 1 electron in the 2nd shell (L-shell).
- **Q (Ne)**: Full outer shell (not likely to lose electrons).
- **R (Mg)**: Has 2 electrons in the 3rd shell (L-shell).
- **S (Ca)**: Has 2 electrons in the 4th shell (not applicable for L-shell).

**Conclusion for (iii)**: Element P (Li) loses an electron from the L-shell.

### Step 4: Determine which element loses electrons from the N-shell
- **P (Li)**: 2nd shell (not applicable).
- **Q (Ne)**: 2nd shell (not applicable).
- **R (Mg)**: 3rd shell (M-shell).
- **S (Ca)**: 4th shell (N-shell).

**Conclusion for (iv)**: Element S (Ca) loses electrons from the N-shell.

### Final Answers:
1. (i) P and Q
2. (ii) R and S
3. (iii) P
4. (iv) S