Since the direction is not specified, it can be safe to assume that the direction of rotation is counterclockwise.
300 degrees is 60 degrees less than 360 degrees, which is a full rotation. Thus, 300 degrees counterclockwise is the same as 60 degrees clockwise.
Note that this shape is a hexagon. Thus, we can divide a hexagon into 6 equilateral triangles, each with measures of 60 degrees. Just move OQ to the adjacent clockwise equilateral triangle and see what it overlaps with.
OQ is the altitude of the equilateral triangle, so our answer will be the altitude of the adjacent clockwise equilateral triangle.
The answer is OF.