Answer:
b. Interval estimation
Step-by-step explanation:
There are two types of estimations for each population parameter; the point estimation and confidence interval (CI) estimation.
The point estimation involves the use of sample data to calculate a single value which serve as a best estimate of an unknown population parameter.
The interval estimation is the use of sample data to calculate range of possible values of an unknown population parameter.
Therefore, the correct option is "b"
b. Interval estimation