In the lochner v. new york case of 1905, the supreme court ruled that states could not
a. pass labor laws to protect women.
b. increase protections for children.
c. pass laws concerning workplace safety.
d. regulate working hours.

In the Lochner v. New York case of 1905, the Supreme Court ruled that states could not regulate working hours. Option D is correct.

Lochner v. New York, 198 U.S. 45 (1905), was a outstanding U.S. labor law case in the US Supreme Court, which stated that limits to working time violated the Fourteenth Amendment.

The Fourteenth Amendment to the United States Constitution was passed on July 9, 1868, as one of the Reconstruction Amendments.

powers  are  denied  to the  national governmentin three distinct ways: some  powers, such as the  power  to levy duties on exports or prohibit the freedom of religion, speech, press, or assembly, are expressly  denied  to the  national government  in the  constitution.