Which of the following cephalosporins is classified as a true second generation?

Cefaclor is indeed classified as a true second-generation cephalosporin. This class of antibiotics was developed to have improved effectiveness against gram-negative bacteria compared to first-generation cephalosporins. Second-generation cephalosporins, including cefaclor, have a broader spectrum of activity, which enables them to target a variety of infections.

Cefazolin is a first-generation cephalosporin, primarily effective against gram-positive bacteria, and is commonly used for surgical prophylaxis. Ceftriaxone is a third-generation cephalosporin with a wider range of activity against gram-negative organisms and is particularly effective against infections caused by organisms resistant to earlier generation cephalosporins. Cefepime, on the other hand, is a fourth-generation cephalosporin that combines the properties of the third-generation cephalosporins with improved efficacy against gram-positive bacteria.

Thus, the classification of cefaclor as a true second-generation cephalosporin aligns well with its intended use and the bacterial targets it is designed to address, distinguishing it from the first, third, and fourth-generation cephalosporins mentioned in the other choices.