The correct answer is option 4: 1 and 4.

Let`s dissect each statement to understand why option 4 is correct:

1. It is fixed at a given temperature: This statement is incorrect. Latent heat is not fixed at a given temperature. It actually changes with temperature.

2. It depends upon the temperature and volume: This statement is incorrect as well. Latent heat does not depend on the volume of the substance. It only depends on the temperature.

3. It is independent of temperature and volume: This statement is incorrect. As mentioned before, latent heat depends on the temperature of the substance.

4. It depends on the temperature but independent of volume: This statement is correct. Latent heat only depends on the temperature of the substance and is not affected by the volume.

Therefore, the correct answer is option 4, which states that statement 1 (It is fixed at a given temperature) and statement 4 (It depends on the temperature but independent of volume) are correct.