Suppose that one of every 500 people in a certain population has a particular disease, which displays no symptoms. A blood test is available for screening for this disease. For a person who has this disease, the test always turns out positive. For a person who does not have the disease, however, there is a 2 \% false positive rate - in other words, for such people, 98 \% of the time the test will turn out negative, but 2 \% of the time the test will turn out positive and will incorrectly indicate that the person has the disease. Let p be the probability that a person who is chosen at random from this population and gets a positive test result actually has the disease. Which of the following is closest to p ?

**Answer Choices**

A. \dfrac{1}{98}

B. \dfrac{1}{9}

C. \dfrac{1}{11}

D. \dfrac{49}{99}

E. \dfrac{98}{99}