43. Laoshas a land area about the same as GreatBritain
but only four millionin population,where many are
members of hill tribes ensconced in the virtually
inaccessible mountain valleys of the north.

(A) about the same as Great Britain but only four
million in population, where many
(B) of about the same size as GreatBritain is, but in
Laos there is a population of only four million,
and many
(C) that is about the same size as GreatBritain's
land area,but in Laos with a population of only
four million people, many of them
(D) comparable to the size of Great Britain, but only
four million in population, and many
(E) comparableto that of GreatBritain but a
population of only four million people,many of
whom

OA: E
I am wondering why them in choice C has an unclear reference?