【语法指代问题Nobodyknowsexactlyhowmanylanguagesthereareintheworld,partlybecauseofthedifficultyofdistinguishingbetweenalanguage(andthesublanguagesordialectswithinit,butthosewhohavetriedtocounttypicallyhavefound)】

　　语法指代问题

　　Nobodyknowsexactlyhowmanylanguagesthereareintheworld,partlybecauseofthedifficultyofdistinguishingbetweenalanguage(andthesublanguagesordialectswithinit,butthosewhohavetriedtocounttypicallyhavefound)aboutfivethousand.

　　(A)andthesublanguagesordialectswithinit,butthosewhohavetriedtocounttypicallyhave

　　found

　　(B)andthesublanguagesordialectswithinthem,withthosewhohavetriedcountingtypically

　　finding

　　(C)andthesublanguagesordialectswithinit,butthosewhohavetriedcountingittypicallyfind

　　(D)orthesublanguagesordialectswithinthem,butthosewhotriedtocountthemtypicallyfound

　　(E)orthesublanguagesordialectswithinthem,withthosewhohavetriedtocounttypicallyfinding

　　这里C的第二个it为什么不对?OG说应该用复数them