What is the term used to allow a company with a radioactive material license in one state to work in another state?

The correct term that allows a company with a radioactive material license in one state to work in another state is reciprocity. This concept involves the agreement between states to honor each other's licenses and regulatory standards regarding radioactive materials. It facilitates the movement and operation of licensed entities across state lines without the need for duplicating the licensing process in the second state.

Reciprocity is particularly important for companies involved in activities like construction, maintenance, or research that may require the use of radioactive materials in various locations. This streamlined approach helps promote efficiency while ensuring that all operations remain compliant with necessary safety and regulatory standards.

The other options do not accurately capture the established legal framework that allows for such interstate operations. For instance, "Transfer License" suggests a transferring of licenses rather than mutual recognition, while "Interstate License" and "Mutual Agreement" lack the specific legal foundation that reciprocity provides in the context of radioactive material usage across state lines.