Based on This Map, Why Were the Egyptian and Mycenaean

Based on this map, why were the Egyptian and Mycenaean Greek civilizations especially susceptible to invasion by the Sea Peoples?
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A) They lacked significant walls and other structures to deter such invasions.
B) They bordered waterways, which is how the Sea Peoples traveled.
C) They had only deserts as deterrents, which the Sea Peoples traveled through easily.
D) They lacked the dense forests from which other kingdoms and regions benefitted.