The u. s. clean air act amendments of 1990 require the:

a. development of automobiles with lower nitrogen oxide and hydrocarbon emissions.
b. construction of more mass transit systems.
c. elimination of diesel-fueled vehicles.
d. reduction of automobile traffic.
e. reduction of air pollutants in agricultural and rural areas.

A. development of automobiles with lower nitrogen oxide and hydrocarbon emissions.

Explanation:

This act implements a comprehensive program to reduce air pollution to protect human health and environment, the amends made in 1990 focused on problems of acid rain, ozone depletion, and toxic air pollution, they established new auto gasoline reformulation requirements and set the Reid vapor pressure standards to control evaporative emissions from gasoline.

d is the correct answer.

b is incorrect because it makes food by itself

c is incorrect because us humans don't know how to produce their own food using the sun like plants.

a is incorrect because consumers can depend on carnivores for eating food for consumers to eat the dead organism. same thing with omnivores.

so you know what happened be fore you were alive

explanation: