Safer - yet- effective alternatives remain elusive. Ironically, the idea that pyrethroids are safer that DDT is unproven. Almost no studies on health risks of pyrethroids exist; thus, we cannot guarantee their safety. We can, however, guarantee the spread of malaria without DDT. Why does Velasquez include the detail about the lack of studies about the health risks of pyrethroids?

a. to emphasize the danger of allowing malaria to spread.
b. to highlight that the world needs safer malaria preventions
c. to clarify why some nations have to fight malaria using DDT
d. to strengthen the case for using DDT to prevent malaria