(01.05 MC)Which of the following best describes the location of the first river valley civilizations?

Civilizations developed in locations ideal for trade with natural defenses to prevent attack.
Civilizations developed in remote areas so that they did not have to spend tax money on defense walls.
Civilizations developed in areas well suited for agriculture but relied on trade for everything else.
Civilizations developed in areas ideal for trade but low in natural resources and defenses.