A Researcher Develops a Brief Questionnaire Measure of People's Level

Multiple Choice

A researcher develops a brief questionnaire measure of people's level of optimism.To determine whether his measure is a good one,he asks a sample of people to complete his questionnaire twice,separated by one month.At the second session,he also asks his participants to complete another measure of optimism-one that has been an accepted measure of optimism for many years.Using this procedure,the researcher is establishing the

A) independent variable of optimism.
B) precision and accuracy of his measure.
C) reliability and validity of his measure.
D) nomothetic and idiographic features of optimism.