Identify the non-probability samples from the following. Choose the correct answer from the options given below.

1.Simple random sample

2.Quota sample

3.Systematic sample

4.Snowball sample

A2, 3 and 4 only

B3 and 4 only

C1, 2 and 3 only

D2 and 4 only ✓ Correct

Correct answer: (D) 2 and 4 only

Explanation

Quota sampling and snowball sampling are non-probability methods, so statements 2 and 4 are correct.

In quota sampling the researcher fills preset category targets by convenient selection.

Snowball sampling recruits further participants through referrals from existing ones.

Simple random sampling gives every unit a known equal chance, making it a probability method.

Systematic sampling picks every kth unit from a list and is also probability based.

Non-probability samples limit generalisation because selection probabilities are unknown.

Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.