In a certain code, 'RAT' is coded as '181920'. How would 'BAT' be coded if 'B' is 2, 'A' is 1, and 'T' is 20?

Answer: A. 2120
The code for 'BAT' is formed by concatenating the values of B, A, and T: 2, 1, and 20, resulting in '2120'.