Nina is 10 years younger than Deepak. Deepak is 3 times as old as Nina. Which system of equations can be used to find d, Deepak's age, and n, Nina's age?
Ad = n + 10 d = 3n
Bd = n − 10 d = 3n
Cd = n + 10 n = 3d
Dd = n − 10 n = 3d
Ad = n + 10 d = 3n
Bd = n − 10 d = 3n
Cd = n + 10 n = 3d
Dd = n − 10 n = 3d