In the event of isolation during operations other than war, the reasons to delay contact with legitimate authorities include:
1.Gain situational awareness
2.Contact friendly forces
The Chaldean Empire began on 605 B.C. and they claimed many lands that once belonged to the Assyrians, but Egypt was not one of them.
By the time that the Chaldean Empire started, it also started an alliance between the Assyrians and Egyptians to fight the Babylonians.
They both had their armies destroyed. Assyria was never to be recognized again as an independent power and Egypt retreated, becoming insignificant for a while.
Egypt used Greek mercenaries to get rid of the domain that the Assyrians had over them and they did go through a prosper time, but it for the Persians to show up and dominate them in the 500s B.C.
For resources and to prove that they were powerful. Their initial holdings before WW2 were not enough to fuel the war machine it wanted to become.
The answer is B.
They were conquered by Sargon who was then called the Great Akkad