3. If $3 x^{3}-k x^{2}+4$ is divided by $3 x-1$ and the remainder is 3, then the value of $k$ is ( ).
(A) 2
(B) 4
(C) 9
(D) 10
3.D.

Given that $3 x^{3}-k x^{2}+1$ can be divided by $3 x-1$, then $3 \times\left(\frac{1}{3}\right)^{3}-k\left(\frac{1}{3}\right)^{2}+1=0$.
Thus, $k=10$.