Answer: C
Step-by-step explanation:
The best reason for inserting the gene that controls the production of the insecticidal substance into corn plants is:
C. Fewer pesticides will be needed.
By inserting this gene into corn plants, the plants will produce the insecticidal substance, which will protect the corn from insects without the need for additional pesticides. This reduces the amount of chemicals that need to be applied to the crops, making it more environmentally friendly and potentially reducing the exposure of humans to harmful pesticides.