This coin (1799 $10 gold piece) was listed on eBay for over $20,000 this month. Which of the following is a true statement?
A. The transaction cost of buying this coin would in part be research into its authenticity.
B. If this coin sells for more than $20,000 it will reflect the role of the invisible hand.
C. No one controls the market for old coins, so the value of this coin is based on mutual agreement.
D. The internet has lowered the transaction cost of shopping for old coins.
E. All of the above.