Each of these major rivers is associated with great population clusters having very high densities except one, which is it?

a. Ganges
b. Huang (Yellow)
c. Indus
d. Mississippi

Look in the Atlas for those rivers and you can see which ones have the most towns/cities on them.

http://www.infoplease.com/atlas/

To find the answer to this question, you can use an Atlas that provides information about the major rivers and population clusters associated with them. One such Atlas is Infoplease, which provides detailed maps and information about rivers around the world.

Here are the steps to find the answer using Infoplease Atlas:

1. Go to the website http://www.infoplease.com/atlas/.
2. Once on the website, locate the search bar at the top right corner.
3. Enter the name of the first river, "Ganges," in the search bar and click on the search button.
4. The search results will display a map along with relevant information about the river and its associated population clusters.
5. Repeat steps 3 and 4 for the remaining rivers - "Huang (Yellow)," "Indus," and "Mississippi."
6. Compare the results for each river and identify the river that is not associated with a high population cluster.

By following these steps and examining the information provided for each river on the Infoplease Atlas, you will be able to determine which major river is not associated with a high population cluster.