Nutritionists at a Large University Investigating the Impact of Dining

Nutritionists at a large university investigating the impact of dining hall food choices on freshman weight gain collected data (through weekly surveys) from 300 students throughout their freshman year.They kept track of the student's age,the number of times eating in the hall per week,the number of hours spent exercising per week,and the student's weight each week.

A) Who: Nutritionists; Cases: Each student is a case; What: Student's age,number of times eating in hall weekly,number of hours exercising weekly,and the student's weekly weight; When: Freshman year; Where: A large university; Why: To study the impact of dining hall choices on freshman weight gain; How: Weekly surveys.
B) Who: 300 freshman students; Cases: Each student is a case; What: Student's age,number of times eating in hall weekly,number of hours exercising weekly,and the student's weekly weight; When: During the student's freshman year; Where: A large university; Why: To study the impact of dining hall choices on freshman weight gain; How: Weekly surveys.
C) Who: A large university; Cases: Each student is a case; What: Student's age,number of times eating in hall weekly,number of hours exercising weekly,and the student's weekly weight; When: During the student's freshman year; Where: Dining hall; Why: To study the impact of dining hall choices on freshman weight gain; How: Weekly surveys.
D) Who: Nutritionists; Cases: Each nutritionist is a case; What: Student's age,number of times eating in hall weekly,number of hours exercising weekly,and the student's weekly weight; When: Freshman year; Where: A large university; Why: To study the impact of dining hall choices on freshman weight gain; How: Weekly surveys.
E) Who: 300 students; Cases: Each student is a case; What: Student's age; When: During the student's freshman year; Where: A large university; Why: To study the impact of dining hall choices on freshman weight gain; How: Phone surveys.