Researchers studied 500 people and matched their personality type to when in the year they were born. They discovered that the number of people with a "cyclothymic" temperament, characterized by rapid, frequent swings between sad and cheerful moods, was significantly lower in those born in the spring. The study also found that those born in the summer were less likely to be depressive, while those born in winter were less likely to be excessively positive. Complete parts (a) through (e) below. (a) What is the research question the study addresses? O A. Are people born in winter excessively positive? O B. Does year of birth affect mood? O C. Are people born in summer depressive? O D. Does season of birth affect mood? (b) What is the sample? O A. All people O B. All people born in the winter O C. The 500 people who are excessively positive, depressive, or have mood swings O D. The 500 people in the study (c) What type of variable is the season in which you were born? O A. Quantitative, discrete, interval O B. Qualitative, nominal O C. Qualitative, ordinal O D. Quantitative, continuous, ratio O E. Quantitative, discrete, ratio OF. Quantitative, continuous, interval