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.

not  

cuba  

russia  

iraq  

el salvador  

explanation:

known as the land of volcanoes, el salvador has visit seismic tremors and volcanic movement. it is the main nation in central america that does not have a coastline on the caribbean sea. about portion of all salvadorans live in the wide open. they are poor and don't have power or running water in their homes. in 1525, pedro de alvarado, a lieutenant of cortés's, vanquished el salvador. el salvador, with alternate nations of central america, pronounced its freedom from spain on sept. 15, 1821, and was a piece of a league of central american states until the point when that association broke up in 1838.