Question

Correct the text by inserting one comma.

Although the amount of garbage that goes into landfills has dropped since
1990 the average American today still generates more than four pounds of
garbage every day.

Answer 1

After 1990

Step-by-step explanation:

Although the amount of garbage that goes into landfills has dropped since

1990, the average American today still generates more than four pounds of

garbage every day.

It goes after 1990 because it's running o the idea, but introducing something new :)