问题

Only __ as an interpreter __ how important it was to practise speaking English.
A:when did I workI realized
B:when did I workdid 1 realize
C:when I workdid I realize
D:when I workeddid I realize
B:when did I workdid 1 realize
C:when I workdid I realize
D:when I workeddid I realize
正确答案是: