In a cascade control system, the closed loop transfer function of the inner loop may be assumed to have a single time-constant τ1. Similarly, the closed loop transfer function of the outer loop may be assumed to have a single time-constant τ2. The desired relationship between τ1 and τ2 in a well-designed control system is

• A. τ1 is much less than τ2
• B. τ1 is equal to τ2
• C. τ1 is much greater than τ2
• D. τ1 is independent of τ2