Final answer:
The correct answer is B, stating that doubling the distance from a radiation source reduces the exposure by a factor of 4 based on the inverse square law. Spending twice the time in a radioactive area leads to twice the exposure, not four times, making statement A incorrect.
Step-by-step explanation:
The correct answer to the question 'Which of the following is true?' is B. The statement 'If the distance from the radiation source is doubled, radiation exposure drops by a factor of 4' is true. This is based on the inverse square law of radiation which states that the intensity of radiation exposure is inversely proportional to the square of the distance from the source. Therefore, doubling the distance from the source decreases the exposure by a factor of 4.
On the other hand, the statement A, 'If you spend twice the time in a radiation location, you get 4 times the exposure' is not correct as radiation exposure is directly proportional to the time spent in the radiation environment. Thus, if you spend twice the time, you will get twice the exposure, not four times. As a result, the both statements A and B being true (option C) and neither A nor B being true (option D) are incorrect.
Types of work that are likely to cause an increase in the radiation exposure of a worker include occupations in medical imaging, nuclear power plants, radiopharmacy, industrial radiography, and research laboratories where radioactive materials are used.