After adopting broadband internet access, wireless personal

I think its B
junior staff members in the claims department

A. which doubles to 250 the junior staff in the claims department
B. doubling to 250 the number of junior staff members in the claims department
C. which doubles to 250 the junior staff of the claims department
D. doubling to 250 the number of junior staff members of the claims department
E. which doubles to 250 the junior staff in the claims department that

D.
You need to modify the independent clause - so it is either B or D. D is more idiomatic.
"Which..." wrongly modifies the noun preceding it - i.e. "employees"

agreed
members "of" is CORRECT

No, You were right on the first go.

How many members are in the claims department?

How many members are of the the claims department?

It is B for me.

the usage of which in A,C and E wrongly modifies employees and hence are wrong.
That leaves B and D. my choice is B bcos members in claims depptt is more idiomatic.
eg. the number of memebers in claims deptt has doubled
or
the number of members of claims deptt has doubled

B. ...junior staff members in the claims department working from home - i dont understand how members can be both "in the department" and "working from home". At best, it is ambiguous
D. ...junior staff members of the claims department working from home this clears the above contradiction

what is the source of the question?

I think you are changing the subject of the sentence.

the number of people in department X is 25.

people of department X are very intelligent

Ans: B

employees is countable: One employee, two employees, three employees; therefore, the number of should be included in the answer.

This eliminates: A,C,E

Also-don't know if this is correct but
Weston insurance has hired thus the result of this hiring is usually followed by a verb with an -ing ending.

B/D: The split is between in the claims dept and of the claims dept...in the claims dept is correct because in the claims dept is correctly used

After adopting broadband internet access, wireless personal digital assistants, and super-fast home PCs, Weston Insurance has hired new employees, which doubles to 250 the junior staff in the claims department working from home.

(A) which doubles to 250 the junior staff in the claims department
(B) doubling to 250 the number of junior staff members in the claims department
(C) which doubles to 250 the junior staff of the claims department
(D) doubling to 250 the number of junior staff members of the claims department
(E) which doubles to 250 the junior staff in the claims department that

"Members of" is right and not "members in".

As we always hear.. Members of the parliament, or member of the base ball team.

I agree that B is the correct answer but i would like to know in what cases does which refers to noun preceeding it ? I belive - there are some cases where which does not refers to noun preceeding it. At the moment i do not have an example, but i will try to lookup such cases.

Thanks in advance !

got it right . so happy since I am a non-native speaker.

To get a better picture of the sentence, take out "of junior members" since we're more concerned about "the number."

B. doubling to 250 the number (take out: of junior staff members) in the claims department

D. doubling to 250 the number (take out: of junior staff members) of the claims department

B sounds right.

D. I have got the answer by elimination, but I am confused with word "doubling"- it's simple gerund or participle? I think it's simple gerund. Can somebody try to explain this?

which cannot be used because its the incorrect modifier so eliminate the three options , In is the correct usage..so ans B

IMO-D
Can any instructor help in clearing this dilemma ?
I'll be thankful.

By the time SC gurus reply, let me give it a shot
both are prepositions
when it specifies to the number of members(i mean when we want to express the number ) we use in
for eg The number of members in senate has risen to 56.
however, when the emphasis is on the action, we use of
the members of Senate were also present.
That's my
_________________

can anyone tell me the source of this question ...

Both "in" and "of" are prepositions that modify place. Though, it's more idiomatic to say someone "in the department" not someone "of the department". Besides, I think the preposition "of" typically introduces a place on map or a proper noun - "Prince of Egypt" vs. "Prince in Egypt." Sounds a bit better to me.

https://rwc.hunter.cuny.edu/reading-writing/on-line/prep-def.html

That's my take.

I think both B and D are fine, but perhaps the repeating "of" when they are very near doesn't sound nice compared to B.