Answer:
Spores transported by the air.
Step-by-step explanation:
Hello,
In biology, molds account for masses of mycelium, that is vegetative filaments or hyphaes and fruiting structures, produced by various fungi like Aspergillus, Penicillium, and Rhizopus. Such fungi, are associated with food spoilage and plant diseases, therefore, when they reproduce, they release spores which are spread to the air and subsequently transported to suitable sources of substrate allowing them to grow again. In such a way, since the jar was uncovered, spores transported by the air were allowed to get into the soup and grow there.
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