We can "eyeball" the equation . . .
The ellipse . .is:
(A) A vertical ellipse with foci at
(B) A horizontal ellipse with foci at
(C) An ellipse with a minor axis of length 8
(D) An ellipse with a major axis of length 6
We see that the major (longer) axis is in the y-direction, a "vertical" ellipse.
. . The length of the major axis is 8; the minor axis has length 6.
This eliminates answer-choices