Many plant varieties used in industrially developed nations to improve cultivated crops come from less-developed nations. No compensation is paid on the grounds that the plants used are "the common heritage of humanity." Such reasoning is, however, flawed. After all, no one suggests that coal, oil, and ores should be extracted without payment.
Which of the following best describes an aspect of the method used by the author in the argument above

A．The author proceeds from a number of specific observations to a tentative generalization.

B．The author applies to the case under discussion facts about phenomena assumed to be similar in some relevant respect.

C．A position is strengthened by showing that the opposite of that position would have logically absurd consequences.

D．A line of reasoning is called into question on the grounds that it confuses cause and effect in a causal relation.

E．(E) An argument is analyzed by separating statements of fact from individual value judgments.

铁及其化合物在生产生活中应用广泛。

（1）铁矿石是工业炼铁的主要原料之一。下列铁矿石中属于氧化物的是      （填字母）。

其中以磁铁矿石为原料炼铁的化学方程式为         。

（2）铁红是红色的颜料，其成分是Fe₂O₃。将一定量的铁红放入适量稀盐酸中，反应的化学方程式为         。向反应后的溶液中加入一定量铁粉，铁粉消失，溶液变为浅绿色，反应的化学方程式为         。

（3）氯化铁溶液常用作印刷电路板的腐蚀剂，其过程发生如下2FeCl₃+Cu =2FeCl₂+CuCl₂。取反应所得氯化亚铁和氯化铜的混合溶液，加入一定量的锌粉，有如图所示的反应关系。

则下列说法正确的是         （填字母）。

A．向反应后的固体中滴加稀盐酸，一定有气泡产生

B．反应后的溶液中一定没有氯化亚铁

C．反应后的溶液中一定没有氯化铜

D．反应后的固体中一定含有Cu、Fe、Zn