b, f, h.
The bacteria that you would not use a Gram stain on are Escherichia coli, Pseudomonas spp. and Clostridium spp, and Neisseria meningitidis.
Gram-negative bacteria have cell walls with thin layers of peptidoglycan and high lipid content.
This causes them to appear red to pink under a Gram stain.
Gram-negative bacteria include:
Thus, the bacteria that you would not use a Gram stain on are Escherichia coli, Pseudomonas spp. and Clostridium spp, and Neisseria meningitidis.
Learn more about gram negative bacteria here: https://brainly.com/question/1194544
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