Answer: 9/13 ==> A
Explanation:
sin is between 0 and 1 if 0° < theta < 180° ==> sin is positive when y is positive
sin is between -1 and 0 is 180° < theta < 360° ==> sin is negative when y is negative
sin theta * csc theta = 1
sin theta * 13/9=1
sin theta * 13/9 * 9/13 = 1 * 9/13
sin theta = 9/13 ==> A