A.I. Explanation:

Option 1: "Dating back 10,000 years, Cheddar Man is Britain's oldest complete skeleton."

Explanation: While the text states that Cheddar Man is Britain's oldest complete skeleton and is estimated to be 10,000 years old, this statement does not address the author's main conclusion about the implications of Cheddar Man's appearance in relation to modern Europeans.

Option 2: "Cheddar Man's DNA revealed his skin and eye colour."

Explanation: This option is true as per the text, which mentions that DNA allowed researchers to reconstruct Cheddar Man's face, revealing his skin and eye color. However, it does not encapsulate the broader conclusion regarding the differences between ancient Britons and modern Europeans.

Option 3: "Researchers were able to extract and analyse DNA from Cheddar Man."

Explanation: Although the text indicates that DNA was extracted from Cheddar Man, this option focuses on the process rather than the conclusion drawn from the findings. It fails to connect to the main idea about the differences in appearance between ancient and modern populations.

Option 4: "Cheddar Man shows how ancient Britons looked different from modern Europeans."

Explanation: This option accurately reflects the author's main conclusion. The text discusses how Cheddar Man had dark skin and blue eyes, contrasting with the lighter skin associated with modern Europeans, thus highlighting the evolutionary changes over time.