Question

the root greg means group. what does the word aggregation mean? a dangerous or hostile environment an ordering of events a collection of different things

Explanation:

The root "greg" means "group". The word "aggregation" has the prefix "ag - " (which can mean "toward" or intensify) and the root "greg" (group) plus the suffix "-ation" (indicating a process or result). So it should relate to a group or collection. The first option is about a hostile environment, the second about ordering events, and the third is about a collection of different things, which matches the meaning related to "group".

Answer:

a collection of different things