The following data is obtained in an experiment that measures the viscosity7 as a function of molecular weight M for a set of polymers ICSIR-JUNE-2013] M (Da) 990 5032 10191 19825 n (kPa-s) 0.28t0.03 30+2 250t10 2000+200 The relation that best describes the dependence of n on M is (a) n M (b) n~MS2 (c)n M (d) n~ M