Answer:
The correct answer is B
Step-by-step explanation:
In letter A, WHOM should be who, as it is the subject of the clause
In letter B, WHOSE should be WHOM, as it is the object of the clause "they selected ........"
In letter C, WHOLE should be who, as it is the subject of the clause.
In letter D, WHOM should be who, as it is the subject of the clause too