What do you call a person who takes a survey?

The person who conducts a survey is called a Surveyor. What do we call the people who take the survey and answer the questions?

I'm not sure that those who conduct surveys of the questionnaire sort are called surveyors (try pollster instead), but you can call the ones who take the survey respondents.

Respondent noun 2 A person who replies to something, especially one supplying information for a questionnaire or responding to an advertisement. ‘most respondents to our questionnaire considered their practices to be in accordance with current medical guidelines’ - ODO

See also the following entry from the same page:

Respondent adjective 2 [attributive] Replying to something. ‘the respondent firms in the survey’ - ODO

Here are some examples of the term in use:

• Why do People Participate as Respondents in a Survey? - Scott Smith, Qualtrics

• 5 Easy Ways to Avoid Survey Fatigue in Your Respondents - Andrea Fryrear, Survey Gizmo

The first word I thought of for this was participant

A google search indicates that others use this term, as well as respondent as suggested by Lawrence