This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
All of the following are true regarding cephalosporins except : 
Select and explain. 
A. Bactericidal agents, B. Active against only gram negative bacteria, C. IIIrd Generation are resistant to B-lactamases from gram negative bacteria, D. ceftriaxone is administered parenterally
B: Active against only gram negative bacteria
Answer: B: Active against only gram negative bacteria 
Explanation: None