Explanation:

The modern convention for the land boundary between Asia and Africa runs along the Isthmus of Suez and the Suez Canal in Egypt. Istanbul's European part is separated from its Asian part by the Bosphorus strait, a 31-km-long waterway that connects the Black Sea with the Sea of Marmara, and forms a natural boundary between the two continents. ... Similarly, Suez, an Egyptian city straddling the Suez Canal, belongs to both Africa and Asia
Hence, option 1 is the correct answer.