Questions 13-15 refer to the following passage.

What can be inferred about the proposed solution mentioned in the final paragraph?

a. Continued experimentation with nuclear weapons could restore the expected carbon-14 content to the atmosphere to ensure accuracy of carbon dating.

b. Alternatives to fossil fuels should be pursued to prevent further interference with carbon dating procedures.

c. Decay rates of isotopes involved in radiometric methods need to be invariable.

d. Carbon-14 levels could be artificially restored to previous historical levels to allow an appropriate basis of comparison.

e. Appropriate technology to implement radiometric methods needs to be engineered.

Transcribed Image Text:

The determination of the age of KNM-ER 1470, a humanoid skull, would add greatly to our knowledge of mammalian evolution. Anthropolo- Line gists originally dated the habilis skull at 3 million (5) years old. This age seemed unlikely because it was older than the age of any known aus- tralophithecines, which are presumed to be the habilis's ancestor. Further attempts to date the skull have led to speculative results.