Two Technicians Are Discussing a Diagnostic Procedure Where a Tire

Two technicians are discussing a diagnostic procedure where a tire and wheel is spun freely with the vehicle on a hoist. Technician A says that if the treads appear to move inward and outward the tire should be balanced. Technician B says that if the treads move inward and outward the tire is defective and should be replaced. Which technician is correct?

A) Technician A only
B) Technician B only
C) Both technicians A and B
D) Neither technician A nor B