E is the Root. When the Root is on the bottom, the chord is said to be in Root Position.
Explanation
Piano Chord Trivia
Some would even go so far as to want to answer F Ab B (not one the choices above). Theoretically, this would be incorrect, since Ab to B is not a "3rd" interval.
Amin7 and Cmaj6 both include: A C E G
Example: Csus would include these notes: C F G
Those participating in ProProach will not only understand this clearly but will be able to apply this concept after completing Lesson #5