Take (1/2) of the coefficient on "x," i.e., (-8/3)....so ....(1/2)(-8/3) = -8/6

To find "c," square this = (64/36) = (16/9) = c

So, the polynomial is x^{2} - (8/3)x + 16/9

And to factor this, we have

[x - 4/3 ] ^{2}

The correct answer is "c"