Final answer:
The historical event being referred to when Caesar arrived in Egypt is likely Caesar's meeting with Cleopatra in 48 BC. Other options such as the founding of Alexandria, the Battle of the Nile, or the fall of the Roman Republic do not align directly with Caesar's trip to Egypt.
Step-by-step explanation:
When the student refers to Caesar's arrival in Egypt, the historical event being referred to is most likely (C) Caesar's meeting with Cleopatra. After chasing his rival Pompey into Egypt, Julius Caesar met Cleopatra in 48 BC. This strategic alliance signified a significant turning point in Roman history as together they mutually strengthened their political power. The other options A) The founding of the city of Alexandria and B) The Battle of the Nile occurred at different times, and D) The fall of the Roman Republic is a larger event that spans several years, not specifically tied to Caesar's arrival in Egypt.
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