Understanding Enzyme Kinetics and Substrate Concentration Effects

Enzymes are biological catalysts that speed up biochemical reactions in living organisms. They function by lowering the activation energy required for a reaction to occur. Consider an enzyme that converts substrate A into product B. When the substrate concentration is increased, the initial reaction rate also increases until it reaches a maximum velocity (V_max). The enzyme's affinity for its substrate is quantified by the Michaelis-Menten constant (K_m), which represents the substrate concentration at which the reaction rate is half of V_max. Understanding these concepts is crucial for appreciating how enzymes operate under different conditions.

Given the information above, which of the following statements about the effect of substrate concentration on enzyme activity is true?