Mathematics Homework Help

A team of students decided on a project that would give them experience with statistical analysis skills as well as some practice in taking vital signs.  They assembled a group of 40 undergraduate students, 20 science majors and 20 majors in other fields. They brought them to a makeshift clinic and measured their blood pressures. What is the most appropriate measure of association to compare the systolic blood pressures between the two student groups__________? (ie relative risk, odds ratio, etc…)