Answer:
The correct answer is: a. Maggots do not arise spontaneously, but from eggs laid by adult flies.
Step-by-step explanation:
- The meat in the open jars can be directly accessed by the adult flies for consumption. While accessing the food, some of these adult flies can lay egg into the jars which hatch to give rise to new maggots.
- The meat in jars closed by a gauze is exposed to the air but cannot be accessed by the adult flies as the flies are prevented from entering into the jar due to the presence of the gauze. As a result of this the flies do not consume meat, nor do they lay eggs and so no maggots will appear in this jar.