The correct option is C -1000
A digit will be the code of letter if both are present in the same rows and also absent in the same rows.
So, Code of B is 5 as both are present in row number (i), (ii), (iii) and (v) and absent in row number (iv).
Code of E is 1 as both are present in row number (i), (iii) and (v) and absent in row number (ii) and (iv).
Code of K is 6 as both are present in row number (i), (ii) and (iv) and absent in row number (iii) and (v).
Code of I is 2 as both are present in row number (i) and (iv) and absent in row number (ii), (iii) and (v).
Code of L is 0 in row number (i) as the code for BIKE is 5261.
Code of N is 3 as both are present in row number (ii), (iv) and (v) & absent in row number (i) and (iii).
Code of P is 4 as both are present in row number (ii), (iii) and (v) and absent in row number (i) and (iv).
Similarly, code of T is 8 from row number (ii).
Therefore, BITE - KITE = 5281 - 6281 = -1000.
Hence, option (C) is the correct answer.