As a Secondary Mathematics Teacher, Hernandez Conducted a Study That

Multiple Choice

As a secondary mathematics teacher, Hernandez conducted a study that explored whether giving children recess prior to testing helped their test performance. For one of the semesters, he sends half of his classes out for 10 minutes of recess prior to testing for the other half, he provides 10 minutes of free time after the test.
-Given the study was conducted in a school, students in the recess condition classes told students in the other classes that they got to do recess before the tests. This is an example of which of the following?

A) History effect
B) Instrumentation bias
C) Treatment diffusion
D) Placebo effect