The graph illustrates how the percentage saturation of haemoglobin with oxygen varies in the blood of a human and another animal. The partial pressure of carbon dioxide is kept constant at $1.0\ \text{kPa}$, and the temperature is kept constant at $25^{\circ}\text{C}$. Which conclusion does the graph support?
- AAt $25^{\circ}\text{C}$ the affinity of haemoglobin for oxygen increases more in humans than in the animal.
- BHaemoglobin in the animal carries less oxygen than haemoglobin in the human.
- COxygen is more easily released from haemoglobin in animal muscle than in human muscle.
- DThe Bohr effect in the haemoglobin of the animal is greater than in human haemoglobin.