challenge: What were the intended aircraft to be powered by the Pratt & Whitney F401 engine?
  
  A. Grumman F-14 Tomcat and Rockwell XFV-12
  B. Boeing F/A-18 Hornet and General Dynamics F-16 Fighting Falcon
  C. Lockheed F-22 Raptor and Northrop Grumman B-2 Spirit
  D. Grumman F-14 Tomcat and McDonnell Douglas F-15 Eagle
  Answer: 