If 'HOUSE' is coded as '8151921', what is the code for 'CAGE' if 'C' is 3, 'A' is 1, 'G' is 7, and 'E' is 5?

Answer: A. 3175
The code for 'CAGE' is formed by concatenating the values of C, A, G, and E: 3, 1, 7, and 5, resulting in '3175'.