Usage of THIS in place of noun

[vamsi.damaraju]

In the 1980s advertising revenues accounted for approximately 40% of operating profits of a typical local newspaper; in the 1990s this proportion increased to 57%.

(A)newspaper; in the 1990s this proportion increased to 57%.
(B)newspaper; in the 1990s they increased by 57%.
(C)newspaper, in the 1990s they increased to 57%.
(D)newspaper; increasing to 57% in the 1990s.
(E)newspaper, which increased to 57% in the 1990s.

Can anyone explain how come (A) is the right answer, even though (A) uses THIS in place of NOUN?
Is this not against the PRONOUN usage rule?

[jnelson0612]

vamsi, this forum is for quant questions; we also have verbal forums which will be more appropriate to this question. Please repost to the appropriate verbal forum, let us know, and we can delete this thread.