Select correct statements(s):

Options

A. We can condense vapours simply by applying pressure
B. To liquify a gas one must lower the temperature below `T_(c)` and also apply pressure
C. At `T_(c)`, there is no distinction between liquid and vapour state hence density of the liquid is nearly equal to density of the vapour
D. All the statements are correct statements

Answer

To solve the question, we need to evaluate the correctness of each statement regarding the gaseous state. Let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement 1: "We can condense vapors simply by applying pressure."**
- This statement is **true**. According to the phase diagram of a substance, increasing the pressure can lead to a phase change from vapor to liquid. When pressure is applied to a vapor at a constant temperature, it can condense into a liquid.

2. **Statement 2: "To liquefy a gas one must lower the temperature below critical temperature and also apply pressure."**
- This statement is also **true**. The critical temperature is the temperature above which a gas cannot be liquefied, regardless of the pressure applied. To liquefy a gas, it must be cooled below its critical temperature and pressure must be applied.

3. **Statement 3: "At critical temperature there is no distinction between liquid and vapor state; hence density of the liquid is nearly equal to the density of vapor phase."**
- This statement is **true**. At the critical temperature, the properties of the liquid and vapor phases become indistinguishable. The densities of the liquid and vapor phases are nearly equal at this point, as they are in equilibrium.

4. **Statement 4: "All the statements are correct."**
- Since Statements 1, 2, and 3 are all true, this statement is also **true**. Therefore, the fourth statement is correct.

### Conclusion:
All statements (1, 2, 3, and 4) are correct. Thus, the correct answer is that all statements are true.

### Final Answer:
All statements are correct.

---