TPO19 閱讀 Succession 單字題目 - 英檢

在TPO19閱讀第二篇 有一題單字題
原文如下

For Clements, the climax was a "superorganism," an organic entity. Even some
authors who accepted the climax concept rejected Clements' characterization
of it as a superorganism, and it is indeed a misleading metaphor. An ant
colony may be 【legitimately】 called a superorganism because its
communication system is so highly organized that the colony always works as a
whole and appropriately according to the circumstances. But there is no
evidence for such an interacting communicative network in a climax plant
formation. Many authors prefer the term "association" to the term "community"
in order to stress the looseness of the interaction.

19. The word 【legitimately】 in the passage is closet in meaning to

(A) Commonly
(B) Broadly
(C) Properly
(D) Officially

有看到答案選C的 也有看到另一個版本的解答寫D
所以想請教大家 C或D哪一個比較恰當
謝謝!!

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