ask two questions,please give me a hand, thanks

flowermay

19. The invention of reinforced concrete, plate glass, and steel in the mid-1800’s (was enabled )architects (to design )and build (extremely tall) constructions,
    A                                   B                           C
(or) “skyscrapers.”
  D
   

7. ______ land and money enabled construction of the Union Pacific railroad to begin from Council Bluffs, Iowa , in 1865.
(A) By the government granting of
(B) Government grants of
(C) For the government to grant
(D) Government grants so that