Field Experiments Often Lack ______ Because It Is Sometimes Difficult

question 17

Multiple Choice

Field experiments often lack ______ because it is sometimes difficult to ensure that all members of the test group are exposed to the treatment.

• A) internal validity
• B) external validity
• C) reliability
• D) substantive questions

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Definitions:

Prefix

An affix placed before a word to modify its meaning, such as re-, un-, or anti-.

-poiesis

A suffix meaning the formation, production, or generation of something, such as in 'hemopoiesis' the production of blood cells.

Suffix

A morpheme added at the end of a word to form a derivative, e.g., -tion, -sion, -ness.

Formation

The process of developing or being formed; in biology, it often refers to the way cells or tissues are created and organized.