Which title best completes the partial outline? 1.
- Natural barriers of large deserts protected it from invaders
-Predictable annual flooding of the Nile River left rich soil behind
-Pharaohs ruled as "king-gods”

Your
a. The Development of the b. Ancient World
B. Civilization of Ancient Egypt
C. The Geography of Ancient Mesopotamia
D. Religion of the Indus River Valley

B. Civilization of Ancient Egypt

Explanation:

The natural barriers that protected Egypt from invasion were the Mediterranean Sea that borders the country to the north, the numerous rapids and waterfalls, known as cataracts, that formed the upper southern section of the Nile River, the expansive deserts to the east and west, and the massive Sahara Desert to the south.

From my own personal knowledge Egypt is very known to have rulers called "pharohs".

Hope this helps!