Radioactive dating is used to determine the age of fossils, and extinct organisms represented only by fossils. Given these facts, what is used to determine the age of extinct organisms among the following options:
- viruses
 - an electron microscope
 - Echinoderm.
 - fossils of Panthera leo
 - genetic material
 - the Sun
 - tectonic plates coliding
 - radioactive dating


 

        radioactive dating 