Why did the colonist feel they needed to write the declaration of independence?

They wanted to set rules for the people, the power may be the peoples' but they needed to set "ground rules". Like owning a house, its your house but you give yourself some rules.

Explanation:

answer; i believe the correct answer is (crops);

in 342 bc j._c. egypt fell into the hands of the persians, under the reign of nectanebo ii

greek city-states unite in a revolt against the persian empire at the beginning of the fifth century bc. j.-c  

from the year 660 or 659 bc ad, cyrus preached the revolt against the medes to deliver the persians.