How do steady state conditions apply to the enzyme-substrate complex concentration while substrate and product concentrations change?

• A. The enzyme-substrate complex concentration and substrate concentration remain constant, while product concentration varies.
• B. The enzyme-substrate complex concentration varies, while substrate and product concentrations remain constant.
• C. All concentrations remain constant under steady state conditions.
• D. The enzyme-substrate complex concentration remains constant, while substrate and product concentrations can vary.

Answer: (D)