Are you in C___ One? Yes ,I am

Are you in C___ One? Yes ,I am A:Are you in Class One or in Class Two?B:_.A:Yes,I am.B:Yes, Are you () Yes i am Are you free Yes,I am, Are you a teacher?Yes,I'am. "You are seven?""Yes,I am seven." .Are you ______?Yes,I am. Are you in Class One?No,I（ ）.I am in Class One. i am in (class one ,grade one )对括号里提问 ( ) ( )are you( i want 英汉单项选择：What class are you in?A:I am in class one.B:I am in C _____class are you in I am in class one A what B which C who What row are you in?I am in--- A ROW ONE B ROW FIRST C FIRST