Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE student (stu_num VARCHAR); CREATE TABLE enroll (stu_num VARCHAR)
### Question:
What is the first name of students who got grade C in any class?
### Answer:
SELECT DISTINCT stu_fname FROM student AS T1 JOIN enroll AS T2 ON T1.stu_num = T2.stu_num WHERE enroll_grade = 'C'