TPO reading part 28-1-12 - 英檢

想請問一下 Reading TPO 28-1-12

(A) It may rise or fall from year to year, depending on annual rainfall.

對應內文:
In particularly wet years, short stretches of an otherwise dry stream-bed may
have flowing water because the water table rises to intersect the land
surface.

year to year, annual 是每年、年度的雨季
wet years應該是 特定較濕的幾年

我首看到annual就刪去了 雖然後續三個選項都明顯的錯但我還是沒看最後選了D

但我想知道為何A是對的...感謝

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