A Researcher Hypothesizes That Hispanic Children Will Do Worse on a Verbal

A researcher hypothesizes that Hispanic children will do worse on a verbal aptitude test than will Asian children. As she administers the tests to each child, she unintentionally gives the Asian children lots of hints and extra time to finish but she has no interaction with the Hispanic children and takes their papers away as soon as the allotted time has passed. This is an example of

A) participant reactivity.
B) the experimenter-expectancy effect.
C) the negative presentation effect.
D) intertreatment interaction.