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Math·Advanced Math·Nonlinear functions

hard

The function $f$ is defined by $f(x)=8x^2+kx-17$, where $k$ is a constant. In the xy-plane, the graph of $y=f(x)$ passes through the points $(r,21)$ and $(2r,123)$, where $r$ is a constant. Which of the following could be the value of $k$?

A

3

B

9

C

102

D

144