Which ancient civilization is known for constructing large burial mounds in the Mississippi River Valley?

a. Aztec

b. Mayan

c. Mound Builder

d. Toltec

c. Mound Builder

The ancient civilization known for constructing large burial mounds in the Mississippi River Valley is the c. Mound Builder civilization.

The ancient civilization known for constructing large burial mounds in the Mississippi River Valley is the C. Mound Builder civilization. To arrive at this answer, you can follow these steps:

1. Start by eliminating options that are not associated with the Mississippi River Valley. The Aztecs and Mayans were civilizations primarily located in Mesoamerica (modern-day Mexico and Central America), so we can eliminate options a. Aztec and b. Mayan.

2. Now, focus on the remaining options, c. Mound Builder and d. Toltec. The Toltecs were a civilization centered in central Mexico, so they are not associated with the Mississippi River Valley.

3. This leaves us with option c. Mound Builder as the most likely answer.

Therefore, the correct answer is c. Mound Builder.