According to Ron Insana in the video "Crypto is one of the largest speculative bubbles I've seen in my career, says Ron Insana", in which of the following ways does the U.S. dollar differ from a cryptocurrency like Bitcoin? Question 31 Answer a. The U.S. dollar is supported by the "full faith and credit" of the United States b. The U.S. dollar is widely used in global trade and foreign exchange transactions c. The U.S. dollar is backed by the $20 trillion economy of the United States d. Each of these answers is correct