You decided to investigate enzyme kinetics in the presence of ciprofloxacin, a different drug candidate. The data show $K_m$ stays the same, but the $V_{max}$ decreases. This suggests
Ciprofloxacin binds to the enzyme-substrate complex, stabilizing it and preventing the release of the product
Ciprofloxacin forms a covalent bond with the enzyme's active site, permanently inactivating the enzyme
Ciprofloxacin mimics the structure of the enzyme's substrate, directly competing for the active site and preventing substrate binding
Ciprofloxacin binds to a site other than the active site, altering the enzyme's shape and reducing its activity