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: Microbiology
Ecthyma gangrenosum is caused by - 
Select and explain. 
A. Pseudomonas, B. Streptococcus, C. Staphylococcus, D. H. influenzae
A: Pseudomonas
Answer: A: Pseudomonas 
Explanation: None