Which Is a Reason That Delayed Approval by the Food

Which is a reason that delayed approval by the Food and Drug Administration (FDA) of newer drugs prior to 1990?
A) The FDA was using outdated guidelines.
B) There was not enough money from the drug companies to support the testing.
C) Drug companies identified a handful of drugs necessary for disease outbreaks.
D) The drug approval process was not supported by the larger federal government sector.