What is the system function for a two pole band pass filter that has the centre of its pass band at ω=π/2, zero its frequency response characteristic at ω=0 and at ω=π, and its magnitude response is 1/√2 at ω=4π/9?

• A. \(0.15\frac{1-z^{-2}}{1+0.7z^{-2}}\)
• B. \(0.15\frac{1+z^{-2}}{1-0.7z^{-2}}\)
• C. \(0.15\frac{1-z^{-2}}{1-0.7z^{-2}}\)
• D. \(0.15\frac{1+z^{-2}}{1+0.7z^{-2}}\)