Bohr effect on hemoglobin oxygen affinity Steps:

• The Bohr effect states that higher CO2 partial pressure shifts the oxygen dissociation curve rightward, reducing hemoglobin's oxygen affinity.
• Without the graph, curve positions (W vs. X) cannot be determined to evaluate shifts.
• Statements 1 and 2 depend on which curve is right-shifted (higher CO2).
• Statements 3 and 4 depend on which curve shows higher saturation at 70 kPa (higher affinity).

Why B is correct:

• Not enough information.

Why the others are wrong:

• A: Graph absent, cannot confirm 1 and 3.
• C: Graph absent, cannot confirm 2 and 3.
• D: Graph absent, cannot confirm 2 and 4.

Final answer: Not enough information.