填入下面一段文字横线处的语句，衔接最恰当的一句是（   ）

    传说中“中国最美的云和梯田”，隐匿于浙西南括苍山脉雾气迷蒙的群峰深处，弯弯绕绕的盘山公路，倏然甩出一角空地。人已在山腰，朝山下的开阔谷底望去，_______。

B

    Do you find it hard to memorize words? You may not be the only one. Now a new study says that you can draw a picture of something to memorize it better.

    Some Canadian (加拿大的) scientists do the study. They first give a group of students a few words such as "apple" or "balloon (气球)". Then they give the students 40 seconds(秒) to memorize them. The students can write the words again and again. They can also draw a picture of the words.

    When the time is over, the scientists ask the students to sing a song. After that, they give the students 60 seconds. The students have to write down as many words as they can remember. Guess what? Those who draw the words do a much better job than those who write them.

    And don't worry if you are not good at drawing. The scientists say the quality (质量) of the drawing doesn't matter (要紧) at all.

$-\frac{1}{3}$的绝对值是………………………（   ）