A) works for the company, the Breakfast Group, so named because during the early years, Eric worked until breakfast, and is also a chartered accountant
>>>> Misplaced modifiers
B) is a chartered accountant and also works for the company, the Breakfast Group, so named because during the early years, Eric worked until breakfast
>>> Sounds OK
C) also works for the company and is a chartered accountant, the Breakfast Group, so named because during the early years, Eric worked until breakfast
>>>>> we generally say ...he does this and also this ....so "also" is misplaced here.
D) is also a chartered accountant for the Breakfast Group, so named because during the early years, Eric worked until breakfast, and works for the company
>>>>> we generally say ...he does this and also this ....so "also" is misplaced here and ofcourse misplaced modifier at the end which is confusing.
E) works for the company, the Breakfast Group, so named because during the early years, Eric worked until breakfast, where she is a chartered accountant
>>>> "where" is modifying the company here and hence it is misplaced.