Answer:
Option d. All of the following are natural resources or byproducts produced in significant amounts in Oklahoma except copper.
Step-by-step explanation:
Oklahoma is a State located in the South Central region of the United States bordered by Kansas, Missouri, Texas, New Mexico, and Colorado. The State produces important amounts of iodine, as it has salt deposits within its territory. It also has an expanding production of helium, and is one of the biggest producers of limestone of the country. Although Oklahoma historically produced copper between 1964 and 1975, the State no longer is involved with metal production.