Which relationship shows a quadratic equation?

Answer:
B and C
Step-by-step explanation:
I don't know what A is, but it does not appear to be a quadratic and its not linea.
B is a quadratic. y = 2*x^2
C is y = x^2 + 1 This is a quadratic as well.
D I don't know what this is either, but it is not a quadratic and it is not linear