Marisol, Timothy, and Zorian each have a machine that purifies water. The two tables show how much purified water Marisol's and Timothy's machines have produced at certain times after pouring water into the machine. ​

Zorian's machine produces purified water at a constant rate that is faster than the rate for Marisol's machine and slower than the rate for Timothy's machine.

Which equation could represent the amount of purified water, , in ounces, that Zorian's system produces after hours?
A
y=15xy=15xy=15x
B
y=9xy=9xy=9x
C
y=8xy=8xy=8x
D
y=6xy=6xy=6x