Which of the following is an example of naturalistic observation in psychological…

Which of the following is an example of naturalistic observation in psychological research?
Question 1 ?options:
A researcher asks coffee shop employs what percentage of customers say “thank you” after receiving their order.
A researcher surveys people walking through the park. They ask the people if they say “thank you” at a coffee shop after they are handed their order.
A researcher sits in a coffee shop. They observe whether or not customers say “thank you” after they are handed their order.