**Core Concept**
Pseudomonas aeruginosa is a Gram-negative bacterium that can cause severe septicemia, particularly in immunocompromised patients. The treatment of choice involves antibiotics that are effective against this pathogen.

**Why the Correct Answer is Right**
The drug of choice in pseudomonas septicemia is an antibiotic that inhibits cell wall synthesis by targeting penicillin-binding proteins. **Cefepime** is a fourth-generation cephalosporin with a broad spectrum of activity, including against Pseudomonas aeruginosa. It is effective against both aerobic and anaerobic bacteria, including those with beta-lactamase resistance. Cefepime achieves high concentrations in the blood and tissues, making it an ideal choice for treating pseudomonas septicemia.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not specify a particular antibiotic that is effective against Pseudomonas aeruginosa.
**Option B:** This option may be incorrect as it could refer to a different antibiotic that is not necessarily effective against pseudomonas septicemia.
**Option D:** This option is incorrect as it does not specify a particular antibiotic that is effective against Pseudomonas aeruginosa.

**Clinical Pearl / High-Yield Fact**
Cefepime is often used in combination with other antibiotics to treat pseudomonas septicemia, especially in patients with severe disease or those who are immunocompromised.

**Correct Answer:** C. Cefepime