Answer:
3- month U.S treasury bills ( B )
Step-by-step explanation:
estimating the average return of a security depends on two factors: which is the time duration of the security and the level of certainty. the longer the time duration of the security the less certain it could be to estimate its return, this is because there would be a series of fluctuations in interest rate as the time is extended and this will be a challenge with estimating a long term government bond.
Estimating a 3-month U.S treasury bill is more certain because the fluctuations of the interest rate will be minimal and easier to predict. hence the greatest degree of confidence will be exhibited in predicting the average return on 3-month U.S treasury bill.