A researcher looked at characteristics of elementary school students and, in particular, observed whether students satisfied any of the following
criteria:
A = The student lived with at least one of their biological parents
B = The student lived with at least one grandparent
C = The student lived with two parents who were legally married
D = The student lived with only one parent
Which of the events above are mutually exclusive? Select all that apply.
1.) A, C
2.) A, D
3.) C, D
4.) B, C

(Side note: I put down options 3&4 but got it wrong, not sure what I’m missing?)