Which statement about the Michaelis-Menten constant ($K_m$) is correct for an enzyme that has a low affinity for its substrate?
- AIt has a high $K_m$ and reaches $V_{\text{max}}$ at a high substrate concentration.
- BIt has a high $K_m$ and reaches $V_{\text{max}}$ at a low substrate concentration.
- CIt has a low $K_m$ and reaches $V_{\text{max}}$ at a high substrate concentration.
- DIt has a low $K_m$ and reaches $V_{\text{max}}$ at a low substrate concentration.