Final answer:
The particular gram-negative bacterium not commonly associated with burn wound infections from the given options is Haemophilus influenzae (H. influenzae), making D the correct choice.
Step-by-step explanation:
The student's question pertains to gram-negative bacteria that are commonly responsible for burn wound infections. Among the options provided, Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli), and Klebsiella pneumoniae (K. pneumoniae) are known to be associated with such infections. These are all examples of gram-negative bacilli where P. aeruginosa is a strictly aerobic bacterium frequently implicated in hospital-acquired infections and E. coli as well as K. pneumoniae which are part of the Enterobacteriaceae family. However, Haemophilus influenzae (H. influenzae) is typically associated with respiratory tract infections and is less commonly involved in burn wound infections. Therefore, the correct answer to the student's question is D. H. influenza.