In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives._x005F_x000D_ "Jim Crow" shuns the mountains for reasons satisfactory to himself; not so the magpie, the raven, and __________ mischief-maker, Clark's nutcracker. All of which keeps the bird-lover from the East in an ecstasy of surprises until he has _____________ accustomed to his changed environment. One cannot help ___________ into the speculative mood in view of the sharp contrasts ______________ the birds of the East and _________ of the West._x005F_x000D_ Â _x005F_x000D_ until he has _____________ accustomed to his changed environment.

• A. became
• B. becomes
• C. to be
• D. become