An increase in the price and a decrease of the quantity of Paclitaxel (an anti-cancer drug) could be caused by which of the following? Select one: O a. an increase in the number of people being diagnosed with cancer O b. a decrease in the number of Pacific Yew trees (the source of Paclitaxel) O c. an increase in the research and development into chemotherapy drugs O d. a decrease in the wages for the workers in the drug labs