**Core Concept**
The haematocrit (Hct) is the percentage of blood volume occupied by red blood cells. It is an essential parameter in calculating blood volume and is influenced by the concentration of red blood cells. The remaining blood volume is composed of plasma.

**Why the Correct Answer is Right**
To calculate plasma volume, we use the formula: Plasma Volume = Total Blood Volume - Red Blood Cell Volume. Red Blood Cell Volume can be estimated from the haematocrit and total blood volume. The average adult total blood volume is approximately 70 mL/kg of body weight. Given the man's weight (60 kg), his total blood volume would be 60 kg * 70 mL/kg = 4200 mL. Since his haematocrit is 40%, the volume of red blood cells would be 4200 mL * 0.4 = 1680 mL. Now, we subtract the volume of red blood cells from the total blood volume to get the plasma volume: 4200 mL - 1680 mL = 2520 mL. To convert this to liters, we divide by 1000: 2520 mL / 1000 = 2.52 L. Therefore, the plasma volume of this man would be approximately 2.52 L.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided.
* **Option B:** This option is not provided.
* **Option C:** This option is not provided.
* **Option D:** This option is not provided.

**Clinical Pearl / High-Yield Fact**
When calculating blood volume, it is essential to remember that the normal total blood volume is approximately 70 mL/kg of body weight, and the haematocrit is the percentage of red blood cells in the blood.

**Correct Answer:** C.