Uncle Scrooge decided to go for an expedition. He goes to the bank and asks the personal loan of $2000. Based on his reputation, Bank approved the loan but ask for some guarantee as it's a part of bank procedure. Uncle Scrooge mortgages his only car whose worth was a whopping $200000. Bank officer laughed at him and approve the loan instantly.
After expedition when Uncle Scrooge returns, bank officer asked him "Are you dumb! You are so rich, why you mortgage such an expensive car?".
Uncle Scrooge replied "...." and bank officer agreed that he's not a dumb.
What did Uncle Scrooge reply to the bank officer?