文章写作中对材料取舍起决定作用的是（ ）。

(单选题)This is the ______ piano on which the musician created some (单选题)These proposals sought to place greater restrictions on the (单选题)The author believes that the incident described in the passa (单选题)According to this passage, bees communicate by ______. (单选题)According to the passage, the willow tree was able to commun (单选题)The willow tree described in the passage protected itself by (单选题)It can be concluded from the passage that caterpillars do no (单选题)After the Englishman explained the idiom, ______. (单选题)Which of the following is TRUE according to the passage? (单选题)“…was shown is an amusing experience.” (The first paragraph)