b. They reduced air strike losses because American communications were no longer intercepted
The Navajo Code was unbreakable by the Japanese interceptors. This is because it required one to learn the code from the Navajo, which there were no Navajo living in Japan in WWII so they were unable to intercept communications
The answer is A as river valley civilizations relied on rivers as a source of life. River valleys like Egypt, Mesopotamia and Xi, the rivers brought silt and made the soil very fertile, it also brought fresh water and fish to eat. People can also move fast using rivers.
Africans resisted, or rebelled, against their position as slaves
