The sudden outbreak of a devastating disease that has not been reporte

Now, I think B might be correct. I just searched the use of whose in the dictionary.

adj.
The possessive form of who.
The possessive form of which.

Usage Note: It has sometimes been claimed that whose is properly used only as the possessive form of who and thus should be restricted to animate antecedents, as in a man whose power has greatly eroded. But there is extensive literary precedent for the use of whose with inanimate antecedents, as in The play, whose style is rigidly formal, is typical of the period. In an earlier survey this example was acceptable to a large majority of the Usage Panel. Those who avoid this usage employ of which: The play, the style of which is rigidly formal, is typical of the period. But as this example demonstrates, substituting of which may produce a stilted sentence.

I went with A. thought we can use whose only with people. but yes whose can be used with either people or things. (source MGMAT SC. page 87)

e.g) the town whose power supply was contaminated.

Firstly , "Whose" can also refer to things, not only human.
Secondly, the "Whose" clause parallels to the "That" clause.

Both of these are in MGMAT SC.

Ruling out A, C and E were straight forward as many posts have mentioned. I got stuck between B and D.

The way I looked at the question to understand the deeper meaning of the problem:

XYZ (representing the subject of this sentence) THAT HAS................AND......WITH.....THAT is NOT PARALLEL.
Why?
On both sides of the AND should be talking about the same subject which is XYZ. But when we use WITH A CAUSE, THAT is describing the CAUSE rather than XYZ.

In Option, B where it goes THAT (HAS..............AND......WHOSE) is parallel and both describe the XYZ subject correctly.

The sudden outbreak of a devastating disease that has not been reported before and which is unknown in cause is a rarity in modern medicine.

(A) which is unknown in cause
"that" should be used instead of "which"

(B) whose cause is unknown

(C) is unknown as to its cause
make the sentence run-on

(D) with a cause that is unknown
not parrallel

(E) unknown in cause
not parrallel

Dear Mod

I didn't get convincing reason why B is right . Could you please clarify.

regards
ravi

It is NOT necessary that when two relative clauses are made parrallel, the relative pronouns that introduce the clauses be the same. It is alright to use one relative pronoun ("that") to introduce one of the clauses and another relative pronoun ("whose") to introduce the other relative clause. In Option B, the following relative clauses are parallel:

1. that has not been reported before
AND
2. whose cause is unknown

,both referring to "disease".

The correct answer is (B) whose cause is unknown

A) unknown in cause is - grammatically incorrect
C) is unknown as to its cause - grammatically incorrect
D) with a cause that is unknown - grammatically incorrect
E) unknown in cause - grammatically incorrect

This statement really hasn't aged well (2020s).

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