Which are thought to have contributed to the decline of the indus valley civilization? select all correct answers. a) the indus river and its tributaries changed course. b) major sandstorms blanketed the cities, forcing people to leave. c) the soil became too salty for crops to grow. d) cities were destroyed by raging fires. e) people moved to more fertile regions of the subcontinent.

The answers are C and E.

c) The soil became too salty for crops to grow;

e) People moved to more fertile regions of the subcontinent.

Explanation:

The Indus River Valley civilization (3300-1300 BCE) used to use salt water on their agricultural system. So, as the times passes the salt overloaded the soil making it inappropriate to grow anything; thus forcing the civilization to move to more fertile regions in order to have more stable and abundant crops.

world bank is the correct answer.

answer; the federal reserve system;