What will happen to a persons respiratory efficiency if they cannot form the pigment hemoglobin?

A)There will not be any change in their efficiency.
B)Their efficiency will increase and they will be able to carry more oxygen.
C)Their efficiency will decrease because they cannot carry as much carbon dioxide.
D)Their efficiency will increase because they will be able to carry more carbon dioxide.
E)Their efficiency will decrease because they will not be able to carry as much oxygen.