Answer:
The correct answer is option D) Scientists can date any radioactive material back only three half-lives; after this, there's not enough parent material left to measure.
Explanation:
It is true that the exact date of a radioactive material which is known to be unstable cannot be precisely determined due to loss of parent material. The radiometric clock takes a while to swing into action because of high temperatures. It begins after a while when the closure temperature of a radioactive material drops to the barest minimum. At this point, Scientists can date any radioactive material back only three half-lives because most of the parent material needed for the experiment will not remain.
