Due to the region’s low level of rainfall, Arizona Marian’s the ____________
of plant and animal life in the country.
(A) affiliation
(B) concentration
(C) alteration
(D) formation
Answer: B
D不行嗎 ？ 查英英字典 formation 可以當組成 放在這裡意思也通順
國學給的解答formation 是用另一個意思 形成 所以不選D

Arizona後面那個字打錯，是maintains空格前面漏打一個字“lowest”整句話：Due to the region’s low levels of rainfall, Arizona maintains the lowest concentrationof plant and animal life in the country.Google查"the lowest formation of animal life"，找不到相關結果，所以沒有「最低組成」這種說法