What is the impact of substrate binding on the trapping of allosteric enzyme subunits in the R state?

• A. Substrate binding has no impact on subunit state.
• B. Substrate binding causes random subunit state changes.
• C. Substrate binding to one subunit traps all subunits in the T state.
• D. Substrate binding to one subunit traps all subunits in the R state.

Answer: (D)