Through which constitutional amendment, Federally Administered Tribal Areas (FATA) were merged with Khyber Pakhtunkhwa?

Q. Through which constitutional amendment, Federally Administered Tribal Areas (FATA) were merged with Khyber Pakhtunkhwa?
(A) 22nd
(B) 23rd
(C) 24th
(D) 25th

The answer is: (D) 25th