对下表中清朝军机处职能(部分)的表述，正确的是（    ）

根据句意，写出括号内所给单词的适当形式。
____ Do you think it's good for you to keep worries to  _______ (your), boys and girls?
____ In China, it's becoming much _______ (hard) for people to pass the driving tests.
____ The government has realized the importance of the _______ (safe) of the children who take a school bus.
____ More and more teachers feel worried about some _______ (teenage) strange behaviour.

如图，小红居住的小区内有一条笔直的小路，小路的正中间有一路灯，晚上小红由A处径直走到B处，她在灯光照射下的影长l与行走的路程S之间的变化关系用图象刻画出来，大致图象是（　　）

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