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:

Stratification

The layering of sedimentary rock or soil with differing characteristics, or the arrangement of society into different social classes or castes.

Temperate Zone

The Earth's regions located between the tropics and the polar circles, characterized by moderate temperatures and distinct seasonal changes.

Mixing

Mixing refers to the process of thoroughly combining two or more substances, achieving homogeneity at a molecular level in various contexts such as chemistry or cooking.

Limnetic Zone

The open, sunlit surface layer away from the shore of a freshwater body, where photosynthesis can occur, supporting a wide range of plankton and fish species.