※ 引述《amysky0205 (=Amy=)》之銘言：
: Macrophages are cells that play a role in the response of the immune system
: of mice and other mammals to invasive organisms such as bacteria. Unlike other
: mice, mice that are genetically incapable of making these particular cells do
: not show elevated levels of nitrates when infected with bacteria. The statements
: above, if true, provide the most support for which of the following
: conclusions?
: A. Mice that are unable either to make macrophages or to make them in
: sufficient numbers will protect themselves from bacterial infections
: in some other way.
:
: B. Mice that show elevated levels of nitrates can easily fight off most types
: of bacterial infections.
:
: C. In mice, macrophages play a role in the production of nitrates or inhibit
: a process by which nitrates are broken down or otherwise eliminated.
:
: D. When a healthy mouse becomes infected with an invasive organism, the
: number of macrophages in the mouse’s body decreases.
:
: E. Injections of nitrates into mice that lack macrophages will not enhance
: the ability of these animals’ immune systems to fight off infection
: OA: C
: (A)(B) 過度推論, don't know it's true or not.
: (E)跟Injections of nitrates無關
: 想請問(D)和正確答案(C)
: 謝謝!
題目是說 Macrophages (簡稱 M) 會跟隨免疫系統 對入侵生物產生反應
而無法產生 M，Nitrates (簡稱 N) 就不會上升
D: 當入侵生物產生，M 就會減少
答案不對點為:
1. 如果是有反應，那數量應該增加，不是減少。
題目可沒說這是在細菌都不見之後發生的事，
所以別當成白血球殺死細菌之後減少的概念來寫
2. 技巧法則: 既然題目把 N 放在後面討論，
答案選項討論 N、M 關係可能性較大
C: M 為製造 N 或避免 N 減少的過程所需元素
答案正確，因為題目說明如果 M 不存在的話，N 就會減少。
可以反之推得，M 存在，N 就不會減少或增加。此答案合理。
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