Cryosurgery, electrosurgery, and chemosurgery are all forms of ____.?

Which type of research involves studying the relationship between factors or variables to determine whether a strong, weak, or no relationship exists between the factors studied?

A) ?Correlational research B) ?Observational research C) ?Descriptive research D) ?Experimental research

____ bias occurs when a sample is selected scientifically, but not all respondents choose to participate and the resulting sample may not be representative of the target population.

A. Survival B. Non-response C. Loss-to-follow-up D. Selection