Answer
$8xy$
Work Step by Step
The greatest common factor of a group of terms is the greatest factor that evenly divides into all terms in the group.
In this case, $8xy$ is the greatest common factor, because it is the largest factor that divides evenly into all 3 terms.
$16xy^{3}\div8xy=2y^{2}$
$24x^{2}y^{2}\div8xy=3xy$
$8x^{2}y\div8xy=x$