'C' in 'C Reactive Protein' stands for:

C-Reactive Protein is a member of the pentraxin family of proteins named for its ability to precipitate the C-substance polysaccharide in pneumococcus. CRP was so named because it was first discovered as a substance in the serum of patients with acute inflammation that reacted with the C- (capsular) polysaccharide of pneumococcus. CAP is another name for the CRP protein. CAP stands for catabolite activator protein; CRP stands for cyclic-AMP receptor protein. This can be the answer here, but it is not given in the options. So the only related option is Capsular Polysacharide in Pneumococcus. Therefore we can select it as answer of this question. Ref: Textbook of Microbiology By Ananthanarayan, 8th Edition, Page 221; Introduction to Genomics By Ahur Lesk, 2007, Page 396