Explanation:
Mr Rose has just retired from teaching. His age is 60 and he is not a risk taker. He has only a saving account in which he managed to save some money during his life. Now he wants to invest his this money, but being a non risk taker, he wants to invest it somewhere where the risk is too low or almost none. So for him, the best option to invest is in treasury bills. He should purchase the Treasury bills for 5 or 10 years according to his choice, and he will enjoy the interest earned on that while keeping the principal amount safe. There would be no risk in investing in Treasury Bills. This will give him a source of income as well. If he doesn't want to have an income through investment, he can also try to zero risk invest, i-e bonds.