The speaker, Professor Davie, __________ for his impressive achievements in physics, was warmly received by all the students in our school.

A．being known

B．known

C．having known

D．to know

余沐休林下习程公敬通公之里先有玠公者成进士于轩岐之术靡不精公尤博学补诸生以馀闲从事于养生家言遂抉其奥得禁方参伍而用之活人甚众业擅一时四方造庐而请者车填咽门公以次按行东之西怨南之北怨病者望之如望岁焉间与余论方技言人秉阴阳既薄蚀于寒暑风霾又侵夺于饥饱嗜欲复戕伐于喜怒女谒身非木石何得不病巨室力易于致医若瓮牅绳枢之子与逆旅迁客不幸惹恙于时仓皇则简之笥中而医师自足是方书重矣外台秘要已验之良法不下于肘后百一欲广布之海内藉余弁首而行余谓病之需良医犹治之待良相美哉越人之言曰上医医国其次医家其次医身夫和静则寿域戾扰则亡征药有养命者有养性者察其虚实审其寒热时其补泄能防于未然导养得理性命自尽何夭枉之有观于身而知国未有不均于哲士而偾于庸人者公妙于上池而推重司马之书因知秘要盖方略之善者也推端见委证治较然卓越群识与素问灵枢合辙推公之志欲使人人得以尽年其仁心为质乎虽然神而明之存乎其人有不泥于秘要也者斯善读秘要者也(选自《外台秘要》明•吴士奇序)

1．给上文断句2．文意理解①玠公认为人得病的原因是什么?②作者为何推崇《外台秘要》？③“神而明之，存乎其人”是何义?其中“其人”具体指何种人?