[求助]GWD11-34

Q34:

Imported into Massachusetts from Europe in 1869, the gypsy moth was used by a French scientist in an attempt at developing a strong strain of silk-producing insects, crossing gypsy moths with adult silkworms.

1. Imported into Massachusetts from Europe in 1869, the gypsy moth was used by a French scientist in an attempt at developing a strong strain of silk-producing insects, crossing gypsy moths with adult silkworms.
2. Imported into Massachusetts from Europe in 1869, a French scientist was attempting to develop a strong strain of silk-producing insects by crossing gypsy moths with adult silkworms.
3. To cross gypsy moths with adult silkworms, in attempting the development of a strong strain of silk-producing insects, a French scientist in 1869 imported the gypsy moth into Massachusetts from Europe.
4. The gypsy moth was imported into Massachusetts from Europe in 1869 by a French scientist attempting to develop a strong strain of silk-producing insects by crossing gypsy moths with adult silkworms.
5. In an attempt at the development of a strong strain of silk-producing insects, a French scientist, importing the gypsy moth from Europe into Massachusetts in 1869 in order to cross gypsy moths and adult silkworms.

KEY:C

why not D?