You run a regression of final exam grades on hours spent studying, and get the following regression equation:

Grade = 94 - 6.2 * Hours_Spent_Studying + error

What is your takeaway from this regression?

Group of answer choices

a) Studying is bad, and causes worse grades.

b) Students don't know how to study very well

c) A few outliers are skewing the results

d) Students who are less confident study more, but still do worse. There is an omitted variable skewing the results.