Option 1 states that Akbar had the Fort of Agra constructed in the 1560s. This statement is correct and is supported by historical records.

Option 2 states that in the 1570s, Akbar decided to build a new capital at Fatehpur Sikri. This statement is also correct, as Akbar did indeed choose Fatehpur Sikri as the location for his new capital.

Option 3 states that Akbar commissioned a white marble tomb of Shaikh Salim Chishti at Sikri. This statement is correct as well, as Akbar did construct a tomb for Shaikh Salim Chishti at Fatehpur Sikri.

Option 4 states that in 1585, Akbar decided to shift the capital back to Agra. This statement is incorrect. Akbar never shifted the capital back to Agra. After the construction of Fatehpur Sikri, it remained the capital until the 1580s when Akbar moved the capital to Lahore briefly before finally moving it to Agra in 1598.

Therefore, the correct statement is that options 1, 2, and 3 are correct. Alert - the correct answer should be 1, 2, and 3 only.