Absolute dating is a technique used to determine the actual age of a rock or fossil, often through methods like radiometric dating.

• A. It estimates the age of rocks by fossil content
• B. It uses relative dating to assign dates
• C. It compares rock layers to determine age
• D. It assigns an actual date using radiometric methods

Answer: (D)

Absolute dating assigns a specific numerical age to rocks or fossils by measuring radioactive decay. It uses isotopes with known half-lives, and by measuring the ratio of parent to daughter atoms in a mineral, you can calculate the time that has elapsed since the mineral formed. Radiometric methods like uranium–lead, potassium–argon, and carbon‑14 illustrate how different clocks work for different time ranges. This is different from relative dating, which only places rocks in a sequence or assigns age ranges based on fossil content or the order of rock layers, without giving an exact year. Since it provides a numeric age through radiometric measurements, it best matches the description of assigning an actual date using radiometric methods.