67.
Your Answer is
Correct Answer is D
Explanation
contrast "different, contrast" refers to the proportion of color blindness in American men and women compared before and after while in the previous article, so item D is correct.
Item A: "conversion, conversion", does not conform to the meaning of the text.
Item B: "Change", does not conform to the meaning of the text.
Item C: "Conflict", does not conform to the meaning of the text.