Final answer:
The active ingredient in Q-San is quaternary ammonium compounds (QACs), which are effective in killing a wide range of microorganisms.
Step-by-step explanation:
The active ingredient in Q-San is quaternary ammonium compounds (QACs). QACs are a type of disinfectant commonly used in the healthcare and food industry. They are effective in killing a wide range of bacteria, viruses, and fungi.