What is the rate expression for physical absorption of a gas A to a liquid based on two film theory? (Where, kAg is the gas film mass transfer coefficient and kAl is the liquid film mass transfer coefficient)

• A. -rA = \(\frac{p_A- H_A C_A}{\frac{1}{a} + \frac{1}{k_{Al}a}} \)
• B. -rA = \(\frac{p_A- C_A}{\frac{1}{k_{Ag} a} + \frac{1}{k_{Al} a}} \)
• C. -rA = \(\frac{p_A- H_A C_A}{\frac{1}{k_{Al}a}+ \frac{1}{k_{Al}a}} \)
• D. -rA = \(\frac{H_A C_A}{\frac{1}{k_{Al} a}+ \frac{1}{k_{Al}a}} \)