Which Is NOT an Example of an Observational Study

question 8

Multiple Choice

Which is NOT an example of an observational study?

• A)Researchers assign participants to teach either older or younger people how to use a computer to test whether participants appear more frustrated teaching older people.
• B)A manager uses sales records to compare the performance of different employees.
• C)A professor studies the relationship between democracy and per capita income using country-level data from the World Bank.
• D)A political scientist uses data from a random sample survey of 2000 US adults to examine the effect of media exposure on people's trust of government.

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Definitions:

Criteria

Conditions or parameters specified in a query or filter to limit which data is retrieved from a database.

Action Queries

Database commands that perform operations such as update, delete, or insert on records in a table according to given criteria, altering the data.

Delete Query

A type of SQL command or query designed to remove records from a database table based on specified conditions.

Update Query

A type of database query that modifies the data in existing records based on specified criteria.