Final answer:
Alfonzo of Naples was attacked at Ovo Castle, Naples. This historical event is not related to other significant historical locations such as Saint Peter's Basilica or Castel Nuovo.
Step-by-step explanation:
The question 'Where was Alfonzo of Naples attacked?' relates to an event in history. The correct answer is A. Ovo Castle, Naples where Alfonzo of Naples was attacked. The other options, Steps of St. Peter's Basilica, Rome, Palace of Santa Maria in Portico, Rome, and Castel Nuovo, Naples, are famous historical sites with their own unique significance.
For example, Saint Peter's Basilica in Rome stands today as a testament to the Renaissance and the original church built by Constantine the Great. Castel Nuovo is another prominent historical site in Naples but not the location of the attack on Alfonzo.