Answer: Stratified sampling.
Explanation:
We know that stratified sampling is a probability sampling method where the researcher divides the whole population into different subgroups known as strata
After that he randomly selects the final categories proportionally from the different strata.
Given statement : The population of a town is divided into three age categories. A random sample of each category is surveyed about voting choices.
Hence, this type of sampling is stratified sampling.