Question

a convenience sample differs from a voluntary sample in that

a convenience sample is structured based on accessibility to the researcher, and a voluntary sample is based on participant interest.

convenience samples survey each participant once, and voluntary samples survey each participant numerous times.

convenience sampling is not a probability - based method, and voluntary sampling is.

Explanation:

To solve this, we analyze each option:

• Option 1: A convenience sample uses participants accessible to the researcher (e.g., people in a mall for a survey), while a voluntary sample relies on participants' willingness to take part (e.g., people responding to an online survey invitation). This matches the definitions.
• Option 2: There's no rule that voluntary samples survey participants multiple times or convenience samples once. This is incorrect.
• Option 3: Both convenience and voluntary sampling are non - probability sampling methods. So this is wrong.
• Option 4: Both are non - probability sampling, so this is incorrect.

Answer:

A. a convenience sample is structured based on accessibility to the researcher, and a voluntary sample is based on participant interest.