Factors that must be kept constant in the experiment to obtain valid results are option (c) i.e, type of antibiotic, nutrient agar, and temperature.
<h3>what are antibiotics?</h3>
A particular class of antimicrobial agents that works against bacteria is an antibiotic. Antibiotic drugs are frequently employed in the treatment and prevention of bacterial infections because they are the most effective type of antibacterial agent for doing so. Bacteria may be killed or have their growth suppressed.
They could harm the bacterial cell directly by attacking the cell wall. These cells can no longer do additional harm to the body since the bacteria cannot attack it. Other antibacterials, such as tetracycline and erythromycin, prevent the germs from multiplying or growing.
Antibiotics limit bacterial growth and replication by interfering with the bacterial cell wall. Because many types of bacteria have cell walls but human cells do not, antibiotics can kill bacteria while sparing human cells.
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