To solve the problem of matching the situations in Column I with the fundamental forces in Column II, we can analyze each situation one by one.
### Step-by-Step Solution:
1. **Force between two protons (A)**:
- Protons are positively charged particles and experience electromagnetic force due to their charge.
- They also have mass, which means they experience gravitational force.
- Additionally, since protons are nucleons (particles found in the nucleus), they experience the strong nuclear force that holds the nucleus together.
- **Match**: A → Q (electromagnetic force), R (strong nuclear force)
2. **Force between two neutrons (B)**:
- Neutrons are neutral particles (no charge) but they do have mass.
- Neutrons are also nucleons, so they experience the strong nuclear force.
- They will also experience gravitational force due to their mass.
- **Match**: B → R (strong nuclear force), P (gravitational force)
3. **Force between pen and finger (C)**:
- The pen and finger both have mass, so they experience gravitational force.
- Additionally, there is an electromagnetic interaction between the molecules of the pen and the finger.
- **Match**: C → P (gravitational force), Q (electromagnetic force)
4. **Tension force in a string (D)**:
- Tension in a string arises due to forces acting on it, which can include gravitational forces if the string is hanging.
- The tension itself is a result of electromagnetic forces acting at the molecular level in the material of the string.
- **Match**: D → P (gravitational force), Q (electromagnetic force)
### Final Matches:
- A → Q, R
- B → P, R
- C → P, Q
- D → P, Q
### Summary of Matches:
- **A)** Force between two protons → **Q)** Electromagnetic force, **R)** Strong nuclear force
- **B)** Force between two neutrons → **P)** Gravitational force, **R)** Strong nuclear force
- **C)** Force between pen and finger → **P)** Gravitational force, **Q)** Electromagnetic force
- **D)** Tension force in string → **P)** Gravitational force, **Q)** Electromagnetic force
