Concept:Enzyme activity depends on stable, favourable conditions, and any harmful change can reduce the reaction rate.
Explanation:Enzymes work best at an optimum
pH.
When the
pH of the medium is altered, the enzyme’s structure may be denatured or its active site may change, causing the reaction to decline.
Attaining the optimum temperature gives maximum activity, not a decline.
Increasing substrate concentration generally increases activity until saturation is reached.
Changes in atmospheric pressure usually do not directly affect enzyme reaction rates.
Answer:B. the
pH of the medium is altered