prep T1-3

[zeta1203]

3. (24275-!-item-!-188;#058&000768)

The prairie vole, a small North American grassland rodent, breeds year-round, and a group of voles living together consists primarily of an extended family, often including two or more litters. Voles commonly live in large groups from late autumn through winter; from spring through early autumn, however, most voles live in far smaller groups. The seasonal variation in group size can probably be explained by a seasonal variation in mortality among young voles.

Which of the following, if true, provides the strongest support for the explanation offered?

(A) It is in the spring and early summer that prairie vole communities generally contain the highest proportion of young voles.
(B) Prairie vole populations vary dramatically in size from year to year.
(C) The prairie vole subsists primarily on broad-leaved plants that are abundant only in spring.
(D) Winters in the prairie voles' habitat are often harsh, with temperatures that drop well below freezing.
(E) Snakes, a major predator of young prairie voles, are active only from spring through early autumn.

答案是E 可是我在看選項看到snakes想說..超過範圍....瞎
那答案 D為何不行阿 主題重心不是在說 季節變化嗎? 那D提到冬天環境差,young prairie voles 不就容易死翹翹嗎?

我知道此題不難,but,請救我....THX

[sa_pot]

我也錯這題，一開始沒看懂，後來的理解如下：

題目說秋末到冬季這段時間vole的數量很多
然而，春季到初秋這段時間vole的數量很少
這個季節性的變化是因為young voles的死亡率

答案E：蛇(young voles的天敵)在春季到初秋這段時間非常活躍--->所以young voles都被蛇吃掉了

[sa_pot]

補充一下
選項D--->時間點不對
因為題目說冬季是vole數量很多的時候
harsh winter 只會造成 vole 數量減少

[Austing]

3. (24275-!-item-!-188;#058&000768)

The prairie vole, a small North American grassland rodent, breeds year-round, and a group of voles living together consists primarily of an extended family, often including two or more litters. Voles commonly live in large groups from late autumn through winter; from spring through early autumn, however, most voles live in far smaller groups. The seasonal variation in group size can probably be explained by a seasonal variation in mortality among young voles.

Which of the following, if true, provides the strongest support for the explanation offered?

(A) It is in the spring and early summer that prairie vole communities generally contain the highest proportion of young voles.
(B) Prairie vole populations vary dramatically in size from year to year.
(C) The prairie vole subsists primarily on broad-leaved plants that are abundant only in spring.
(D) Winters in the prairie voles' habitat are often harsh, with temperatures that drop well below freezing.
(E) Snakes, a major predator of young prairie voles, are active only from spring through early autumn.

答案是E 可是我在看選項看到snakes想說..超過範圍....瞎
那答案 D為何不行阿 主題重心不是在說 季節變化嗎? 那D提到冬天環境差,young prairie voles 不就容易死翹翹嗎?

我知道此題不難,but,請救我....THX

剛打好多都不見了。。。。。吼
那我講我個人認為的重點　　這題是用排除他因來解題的

[foric0822]

The seasonal variation in group size can probably be explained by a seasonal variation in mortality among young voles.

(D) Winters in the prairie voles' habitat are often harsh, with temperatures that drop well below freezing.
(E) Snakes, a major predator of young prairie voles, are active only from spring through early autumn.

答案是E 可是我在看選項看到snakes想說..超過範圍....瞎
那答案 D為何不行阿 主題重心不是在說 季節變化嗎? 那D提到冬天環境差,young prairie voles 不就容易死翹翹嗎?

我知道此題不難,but,請救我....THX

本題的結論是回答問題的關鍵
隨著團體大小會隨著季節變化，也反映了生存率
D 雖然講到冬天如何，但卻無法解釋為了春天到秋天的數量變化
相對來說E 就可以說明春天到秋天數量變化的原因 也可以回答到生存率的問題

[sgoo]

我的思路是這樣：
抓住兩個點：1.mortality among young voles 2. seasonal variation
所以答案要支持 要跟young voles 的死亡率有關，再加上是季節產生的因素即可！
D選項都沒提到young voles ，所以錯
A選項雖然提到young voles 卻沒提及死亡率
正確答案E，蛇都出現在春天跟早秋，會吃掉young voles