The correct answer to the Stretch to Stretch quiz is the stunt is first Legal in Level 4. In the video the back reaches for the top’s seat, but does not maintain contact with the top during the transition. This makes the transition a prep level to prep level release move which isn’t allowed in Levels 1 and 2 due to release moves not being allowed and not allowed in Level 3 due to release moves needing to start at waist level or below.
The reason this skill was used for a quiz is we often see it performed this way in Level 2. The back reaching for the top person, unsuccessfully attempting to maintain contact, does not prevent the skill from becoming an Illegal release move. In order for the skill to be Legal in Level 2 the top must clearly maintain contact with someone on the ground throughout the entire transition.
The explanation is based on the 2017-18 version of the cheer rules dated August 30, 2017.