If \(P=\sqrt{\frac{rs^3}{t}}\), express r in terms of p, s and t

• A.\(\frac{p^2 t}{s^3}\)
• B.\(\frac{p^3 t}{s^3}\)
• C.\(\frac{p^3 t}{s^2}\)
• D.\(\frac{p^ t}{s^3}\)
• E.