Which of the following is/are characteristic of a municipal bond unit investment trust?

1. Additional securities are not added to the trust 2. Shares may be sold at a premium or discount to net asset value 3. Shares are normally traded on the open market (exchange) 4. The portfolio is self-liquidating. a. 1 only b. 1 and 4 c. 2 and 3 d. 2 and 4