'Even exercise professionals concede 'half a point here' (Sentence 2, Paragraph 2) means 'they ______'.
A.
agree that the calories in a small piece of pastry can be difficult to work off by exercise
B.
partially believe diet plays a supporting role in weight reduction
C.
are not fully convinced that dieting can help maintain one's new weight
D.
are not sufficiently informed of the positive role of exercise in losing weight