Which two statements are valid?

Examine the description of the MARKS table:
STD_ID NUMBER(4)
STUDENT_NAME VARCHAR2(30)
SUBJ1 NUMBER(3)
SUBJ2 NUMBER(3)
SUBJ3 NUMBER(3)
SUBJ1, SUBJ2, and SUBJ3 indicate the marks (grades) obtained by a student in the three
subjects.
Which two statements are valid? (Choose two.)

A.
SELECT COUNT(std_id)
FROM marks
WHERE subj1 >= AVG(subj1);

B.
SELECT SUM(subj1), SUM(subj2), SUM(subj3)
FROM marks;

C.
SELECT SUM(subj1 + subj2 + subj3)
FROM marks;

D.
SELECT MAX(subj1, subj2, subj3)
FROM marks;

E.
SELECT SUM(subj1, subj2, subj3)
FROM marks;

F.
SELECT MINIMUM(subj1)
FROM marks;