Use the Guidelines to Evaluate the Study

question 9

Multiple Choice

Use the guidelines to evaluate the study. From the information given, what is the biggest flaw in the study?
-An educational researcher wishes to compare the effectiveness of two different math textbooks. She has the tenth graders at one school use the first book for one year and the tenth graders at another
School use the second textbook for one year. At the end of the year, she gives the same math test to
Both classes and compares the results.

• A)The setting
• B)Selection bias
• C)Participation bias
• D)The source
• E)Confounding variables

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Definitions:

Fraternal Twins

Twins that develop from two different eggs fertilized by two different sperm, resulting in siblings that are genetically distinct.

Extraembryonic Membrane

Membranes forming outside the embryo that support its development, including the yolk sac, amnion, chorion, and allantois in vertebrates.

Keeps Embryo Moist

A function of the amniotic egg or other structures in various organisms to prevent desiccation of the embryo in a terrestrial environment.

Extraembryonic Membrane

Membranes that are not part of the embryo but are essential for the development of the embryo, including the amnion, chorion, yolk sac, and allantois.