If A=\(\frac{Ω_1 (Ω_u-Ω_l)}{-Ω_1^2+Ω_u Ω_l}\) and B=\(\frac{Ω_2 (Ω_u-Ω_l)}{Ω_2^2-Ω_u Ω_l}\), then which of the following is the backward design equation for a low pass-to-band stop transformation?

• A. ΩS=Max{|A|,|B|}
• B. ΩS=Min{|A|,|B|}
• C. ΩS=|B|
• D. ΩS=|A|