Sally has developed an app from an iPhone, called Errand Whizz, which combines a person's to-do list, information about the retail stores where the person shops, and a GPS system. The app produces maps with the most efficient routes for the user's shopping. Sally is trying to decide how to protect her creative work. Which of the following statements are true about this issue?
a. She can protect her invention as a trade secret by locking the plans in a vault and telling only a few people who are sworn to secrecy about the plans.
b. She can protect her invention by copyright by disclosing the basic ideas to the government, but not to the public.
c. If she wants to copyright her invention, she must register the copyright with the U.S. Copyright Office before the app is made public.
d. Both a and c