∵CD⊥AB is at point D.

∴ ,∠ CDA = 90, tanA=CDAD in Rt△ACD,

∴ad=cdtana= 10033= 1003

In Rt△BCD, ∠ CDB = 90, ∠ B = 45.

∴ db = CD = 100m，

∴ AB = AD+DB =1003+100 =100 (3+1) meters.

So choose D.