Religious beliefs and practices, geography around Nile River and the creation of the Rosetta Stone, contributed significantly to the Egyptian security and stability. The only statement that did not contribute the the Egyptian's security and stability is the regular flooding of the Nile River.
All of it except letter D. regular flooding of the Nile River. The nile river at that era is one source of life in Eqypt because the water gives the plants life and also gives them fish to eat, but the flood that was cause of a strong rain destroys the rice fields and also their houses that also need to repair again.