Final answer:
C. Radioactive Yellow II. The label required on a package containing a highway route controlled quantity (HRCQ) is Radioactive Yellow II (C).
Step-by-step explanation:
The label required on a package containing a highway route controlled quantity (HRCQ) is Radioactive Yellow II (C). The radioactive material, such as a radioactive isotope, like carbon-14, is classified into different categories based on the level of radioactivity and potential hazards. Radioactive Yellow II is the specific label used for packages with an HRCQ, indicating a higher level of radioactivity than Radioactive White I or Empty containers, but lower than Radioactive Yellow III.