题目内容：
Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C) and D). Then mark the corresponding letter on Answer Sheet 1 with a single line through the centre.听音频，回答下列问题。 A．The air becomes still.
B．The air pressure is low.
C．The clouds block the sun.
D．The sky appears brighter.
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