In the case of Reed v. Reed from 1971, how did the U.S Supreme Court curb gender discrimination.

a. by arguing for women's right to privacy in their own healthcare decisions
b. by urging the senate and house of representatives to ratify the equal rights amendment
c. by ruling out arbitrary gender classifications with the equal protections clause
d. by mandating gender-based affirmative action policies in the public sector

c. by ruling out arbitrary gender classifications with the equal protections clause