What is a redflag in anti-money laundering

a. An indication that the checking account of a bank customer is overdrawn. b. A warning sign to potential bank customers that a financial institution has been sanctioned for breaches of their anti-money laundering obligations. c. One of the primary colors on the American flag. d. A warning sign indicating a potentially suspicious or risky transaction or activity. e. A signal to money launderers that a particular financial institution will not tolerate money laundering.