38 Ginkgo biloba is said to be effective at boosting memory, but there is also _____ that it may increase the risk of
strokes.
(A) privacy (B) concern (C) modesty (D) regulation
...but there is also (B)concern that it may increase the risk of strokes. 但令人擔心的是它(銀杏)也可能增加中風的風險。(直翻: 但這裡也有令人擔心的事,就是它可能增加中風風險) *concern雖有關注、擔心(v.)之意,但在此應解釋為不可數名詞(Uncountable Noun.),指令人擔心的事物。 如果只知道動詞形式,會認為but it conerns that...才是正解,或口語上覺得應該加個"a" concern較通順,而誤以為這個選項是錯的 reference: Cambridge dictionary