Anewspaper writer will write an article about the mean age of voters. she will estimate by selecting a sample of voters and calculating their mean age.

which method should the writer use to select the sample?
i need an answer asap explain its urgent
select 100 people who voted for the most popular candidate in the last election

select 100 people who voted in the last election and are more than 30 years old

randomly select 100 people who voted in the last election

randomly select 100 people who read the newspaper