## **Core Concept**
The question tests knowledge of cephalosporins, a class of β-lactam antibiotics, and their spectrum of activity, particularly against *Pseudomonas aeruginosa*, a Gram-negative bacterium known for its resistance to many antibiotics.

## **Why the Correct Answer is Right**
Cephalosporins are classified into generations based on their spectrum of activity and resistance to β-lactamases. The fourth-generation cephalosporin, **Ceftazidime**, is notable for its broad spectrum of activity, which includes *Pseudomonas aeruginosa*. This is due to its stability against β-lactamases produced by *P. aeruginosa* and its ability to bind to penicillin-binding proteins (PBPs) in the bacterial cell wall, inhibiting cell wall synthesis.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Cefazolin is a first-generation cephalosporin with a narrow spectrum of activity that does not include *Pseudomonas* species.
- **Option B:** Cefuroxime is a second-generation cephalosporin with a broader spectrum than first-generation cephalosporins but does not cover *Pseudomonas*.
- **Option D:** Cephradine is another first-generation cephalosporin, similar to cefazolin, lacking activity against *Pseudomonas*.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **Ceftazidime** and **Cefepime** are the cephalosporins with anti-pseudomonal activity, making them valuable in the treatment of infections caused by *Pseudomonas aeruginosa*, especially in immunocompromised patients or those with cystic fibrosis.

## **Correct Answer:** C. Ceftazidime.