Question

About 500 million years ago, trilobites such as this were common ______________ that once covered much of Indiana. Violent storms often occurred in the same area and the trilobites were covered quickly by sediment, hidden for hundreds of millions of years.
A. along riverbanks
B. in the sandy plains
C. in warm, shallow seas
D. throughout the mountains

Answer 1

C) in warm shallow seas 
this couldve been found on google