A guidance counselor is interested in what 1st graders in her school perceive as their biggest challenge. She plans on interviewing 26 students. Which of the following describes a convenience sample? O She obtains the records for each first grader that attends the schools and randomly selects 26 students to interview. O She knows that Mrs. Jones class has exactly 26 students so she visits Mrs. Jones class and surveys the students. She sends a survey home with every 1st grader. She then selects 26 of the returned surveys randomly. O She sorts all of the students by last name and for each letter in the alphabet selects a students who last name starts with that letter randomly