According to the study by lloyd johnston and his colleagues at the institute of social research at the university of michigan monitoring the drug use of america's high school seniors in a wide range of public and private high schools, the percentage of the illicit drug use:
a) declined in the late 1990s?
b) was highest during the early 1990s?
c) has been at the same level since 1990?
d) increased significantly between 2000 and 2005?

The percentage of the illicit drug use declined in the late 1990s

Option A

Explanation:

According to a study that was made by Lloyd Johnston about the use of drugs, alcohol by the students of different agrees including young adults, the college students and also a difference in the consumption of drugs by the boys and the girls was shown in the study.

The trends of the study show that there had been a decline in the consumption of drugs or that of alcohol in the time period of 1990s which was at a very high rate in the 1980s.

2b2t

explanation:

2b2t

answer; existed; limited;