This question asks for the incorrectly matched pair. Diwan-i-Mustakhraj was indeed created by Alauddin Khalji (A is correct). Diwan-i-Kohi was Mohammad bin Tughlaq's agriculture department (B is correct). Diwan-i-Bandagan (Slave Department) was Firoz Tughlaq's creation (C is correct). However, Diwan-i-Aiz was not created by Iltutmish - this is the incorrect match.