Enzyme R breaks down protein in the stomach. Four test-tubes are prepared, and each one contains equal amounts of protein and enzyme R. The test-tubes are maintained at different pH values and temperatures. In which test-tube will protein digestion happen fastest?
- ApH 2 at $20\,^{\circ}\mathrm{C}$
- BpH 2 at $35\,^{\circ}\mathrm{C}$
- CpH 7 at $20\,^{\circ}\mathrm{C}$
- DpH 7 at $35\,^{\circ}\mathrm{C}$