Which of the following statements about Ngb-H64Q is true?

a. Ngb-H64Q has a higher affinity than hemoglobin for carbon monoxide, whereas hemoglobin has a higher affinity than Ngb-H64Q for oxygen.
b. Ngb-H64Q has a higher affinity than hemoglobin for both carbon monoxide and oxygen. However, Ngb-H64Q binds to carbon monoxide with a higher affinity than to oxygen.
c. Ngb-H64Q has a higher affinity for oxygen than it does for carbon monoxide.
d. Ngb-H64Q binds to oxygen and carbon monoxide with equal affinity.

b. Ngb-H64Q has a higher affinity than hemoglobin for both carbon monoxide and oxygen. However, Ngb-H64Q binds to carbon monoxide with a higher affinity than to oxygen.

Explanation:

A study of neuroglobin (Ngb),  a hemoglobin-like protein present in the brain, was done at the University of Pittsburgh by a team of researchers. Upon testing the red blood cells of a mouse that contained carbon monoxide, they found that Ngb-H64Q was significantly better at removing CO from hemoglobin than 100-percent oxygen treatment. Hence Ngb-H64Q binds to carbon monoxide with a higher affinity than to oxygen.

true is the answer : )