During an investigation into the antimicrobial properties of garlic extract, a student inoculated an agar plate with Bacillus subtilis. Before incubating the plate at 25 ∘C25\ ^\circ\text{C}25 ∘C, they ensured that the Petri dish was placed upside down (inverted).
Explain why incubating the agar plate in an inverted position is necessary for a valid investigation.
