【单选题】What can we learn from what tile speaker said?
A.
He is a retired teacher of history.
B.
He thinks children were happier in the past.
C.
He lives on a farm far away from cities.
【单选题】豆科植物的干燥根入药,质韧,纤维性强,有纤维性纵皱纹及棕色同心性环纹的药材是
【单选题】抗氧化维生素的抗氧化活性可清除自由基,防止自由基对机体的损伤和致癌,具有抗癌、抗自由基和抗氧化的维生素是