Which radiometric dating method specifically measures the amount of carbon-14 in a sample?

The carbon-14 dating method is specifically designed to measure the amount of carbon-14 present in a sample. This technique is particularly useful for dating organic materials, such as wood, bones, and shells, which are up to about 50,000 years old. Carbon-14 is a radioactive isotope of carbon that is continuously produced in the atmosphere and incorporated into living organisms through processes like photosynthesis and eating.

When an organism dies, it stops taking in carbon-14, and the existing carbon-14 within it begins to decay at a known rate, known as its half-life, which is approximately 5,730 years. By measuring the ratio of carbon-14 to carbon-12 in a sample and comparing it to a standard, scientists can determine how long it has been since the organism died. This method is invaluable for archeology, geology, and other fields that study recent geological events or ancient life on Earth.

The other methods listed are based on different isotopes and apply to dating geological formations or much older materials. For instance, uranium-lead dating and potassium-argon dating are used for much older samples, typically millions of years old, while rubidium-strontium dating is also aimed at dating ancient rocks and minerals. Therefore,