What are the steps of the problem solving process mis?

Icivics worksheet : rules for running a country

As part of the gulf war, the us came to the aid of kuwait during operation desert storm in 1991. which number represents the country that invaded kuwait? a) 2 b) 3 c) 4 eliminate d) 5

This is for my social studies guide and i can answer 21/22 of it perfectly fine. but can someone tell me what the caste system was, and what divisions/classes that it was apart of it?