Answer:
more than 4% but less than 6%
Step-by-step explanation:
Given that the new quotes for a 4% bond trading in the secondary market are higher than 4% which is actually a 6% basis, thus, it is expected that the customer's yield to be greater than the initial 4%. However, given that, we are looking for the customer's yield after-tax, then the net customer's yield will be less than 6%.
Therefore, the right answer is that the customer's yield will be MORE THAN 4% but LES THAN 6%.