Question

the critical turning point for the byzantine empire was 642, when arab invaders captured egypt, the empires crucial grain - producing region. before the 640s, the byzantine empire remained a force to be reckoned with, but after the loss of egypt, every emperor lost territory as their wealth and power diminished.

Explanation:

The text states that 642 was a critical turning - point for the Byzantine Empire as Arab invaders captured Egypt (a crucial grain - producing region). Before the 640s, the empire was powerful, but after losing Egypt, emperors lost territory as wealth and power diminished. This aligns with the statement in the question.

Answer:

True