The correct option is D b - a - c
As per the question given, a+b+c means a>b>c i.e. a is the greatest.
Option A means b<a>c i.e. a is the greatest.
Option B means c<b<a i.e. a is the greatest.
Option C means c<a>b i.e. a is the greatest.
Option D means b<a<c i.e. c is the greatest that is not implied in the question.
Therefore, correct answer is Option D.