Which of the following types of sampling is least likely to have prejudice (bias)?

Simple random sampling is least prone to bias because every unit has an equal chance of selection.

Snowball sampling relies on referrals and produces a skewed sample.

Convenience sampling selects whoever is easiest to reach, inviting bias.

Purposive sampling picks units to fit the researcher's own judgement.

Random selection lets probability theory support unbiased inference.

These non probability methods cannot guarantee representativeness.