Choose the correct statement.

Options

A. Gravitational forces are attractive forces
B. Nuclear forces are attractive forces
C. Electromagnetic forces can be attractive as well as repulsive
D. All of these

Answer

To solve the question, let's analyze each statement provided in the options regarding the types of forces:

1. **Gravitational Forces are Attractive Forces**:
- According to Newton's law of universal gravitation, any two masses attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Therefore, gravitational forces are indeed attractive.

2. **Nuclear Forces are Attractive Forces**:
- Nuclear forces, which act between nucleons (protons and neutrons) in the nucleus, are primarily attractive. These forces help to bind the nucleons together, overcoming the repulsive electromagnetic forces between the positively charged protons. Thus, this statement is also correct.

3. **Electromagnetic Forces can be Attractive or Repulsive**:
- According to Coulomb's law, electromagnetic forces can be either attractive or repulsive depending on the nature of the charges involved. Like charges repel each other, while opposite charges attract. Therefore, this statement is also correct.

Since all three statements are correct, we can conclude that the correct answer to the question is:

**All of these.**

### Step-by-Step Solution:
1. **Identify the nature of gravitational forces**: Gravitational forces are attractive.
2. **Analyze nuclear forces**: Nuclear forces are also attractive, binding nucleons together.
3. **Examine electromagnetic forces**: Electromagnetic forces can be both attractive and repulsive based on the nature of the charges.
4. **Conclude**: Since all statements are correct, the answer is "All of these."