2 half-lives have passed if a sample contains 25% of its original carbon-14.option B is correct.
The act of producing radiation spontaneously is known as radioactivity. This is accomplished by an unstable atomic nucleus that want to give up some energy in order to move to a more stable form.
The half life is found as;
[tex]\rm N=\frac{N_0}{2^n}[/tex]
Archaeologists use radioactive decay of an isotope of the element carbon. Because it has a fairly short half-life, and is found in anything that was once living.
2 half-lives have passed if a sample contains 25% of its original carbon-14.
Hence,option B is correct.
To learn more about the radioactivity, refer to the link;
brainly.com/question/1770619
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