Which of the following is NOT true concerning the curl-up test?A.The curl-up only tests the endurance of the abdominal muscles, not their strength.B.Curl-ups are performed while lying on the floor with knees slightly bent.C.The fingers are supposed to slide 3.5 inches along the floor during a curl-up.D.Curl-ups are supposed to be done at a rate of about one every three seconds.