Answer:
d. All of the last 12 payments he received are taxable.
Explanation:
In the case when the life expectancy is 180 months and collected 192 payments prior he died
So according to the question, all the 12 payments would be received are taxable
Here the payment that received for 180 months would not be involved in the gross income and the remaining 12 payment would be taxable
Therefore the option d is correct