You Read in a Professional Magazine That, in One Research

You read in a professional magazine that, in one research study, researchers obtained a correlation of -.50 between the amounts of time that college students study and the course grades that they earn.You should conclude that:

A) studying helps students earn higher grades.
B) studying interferes with students' class performance.
C) students who study more get higher grades.
D) students who study more get lower grades.