Aresearcher in interested in whether students who are musicians have higher intelligence test scores than students in the general population. the researcher predicts that playing a musical instrument is associated with higher intelligence test scores. the researcher selects a sample of 75 musicians from local high schools and gives them an intelligence test. she compares their average intelligence to that of students in the general population and finds that zobt = +1.92. this is a test and the researcher should conclude
a) one-tailed; that students who are musicians score significantly higher on intelligence tests.
b) two-tailed; that students who are musicians score significantly higher on intelligence tests.
c) one-tailed: that students who are musicians do not score significantly higher on intelligence tests.
d) two-tailed: that students who are musicians do not score significantly higher on intelligence tests.