Your middle-school-aged daughter describes a new female classmate as "different." She tells you that this classmate is quite short but has broad shoulders and a webbed neck. She also says that this classmate is clumsy in gym class and slow in geometry but okay in English. Of the following, which is most likely to be true?
A) Your daughter's new classmate has Klinefelter syndrome.
B) Your daughter's new classmate has trisomy X.
C) Your daughter's new classmate is an XXX female.
D) Your daughter's new classmate has Turner syndrome.

The authors of the paper "fudging the numbers: distributing chocolate influences student evaluations of an undergraduate course"† carried out a study to see if events unrelated to an undergraduate course could affect student evaluations. students enrolled in statistics courses taught by the same instructor participated in the study. all students attended the same lectures and one of six discussion sections that met once a week. at the end of the course, the researchers chose three of the discussion sections to be the "chocolate group." students in these three sections were offered chocolate prior to having them fill out course evaluations. students in the other three sections were not offered chocolate. the researchers concluded that "overall, students offered chocolate gave more positive evaluations than students not offered chocolate." indicate whether the study is an observational study or an experiment. give a brief explanation for your choice.