Of the Following, Which Is a Quantitative Research Problem

Of the following, which is a quantitative research problem?

A) The purpose of the study is to study the characteristics of female students in advanced mathematics courses.
B) The purpose of this study is to examine relationships between future career goals and enrollment in advanced mathematics courses.
C) This study examines what teachers should do to enroll more female students in advanced mathematics courses.
D) The goals of this research were to describe two female students' experiences in advanced mathematics.