When your client performs the sphinx with reach exercise, why is it important to avoid a shoulder shrug in the support arm?/2022

When your client performs the sphinx with reach exercise, why is it important to avoid a shoulder shrug in the support arm?

1. TO MINIMIZE SERRATUS ANTERIOR ACTIVATION
2. TO INCREASE ACTIVATION OF THE ABDOMINALS
3. TO MAXIMIZE SERRATUS ANTERIOR ACTIVATION
4. TO INCREASE ACTIVATION OF THE UPPER TRAPEZIUS