Which of the following groups contains mostly radioactive elements? question 5 options: nonmetals alkaline earth metals halogens inner transition metals

inner transition metals

Explanation:

The inner transition metals consists mostly of the f-block elements. They comprise of lanthanides and actinides. Many of them are radioactive because they possess atomic numbers greater than 82, hence their nuclei are unstable. Many of them are synthetic elements hence they are highly radioactive with very short half lives.