A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A → B. Film mass transfer resistance is negligible and pore diffusion of A is rate controlling. The effectiveness factor of the catalyst is reported as 7/8. Which of the following statement is true?
A. Inner catalyst core of radius R/8 does not participate in reaction
B. Inner catalyst core of radius R/2 does not participate in reaction
C. Inner catalyst core of radius 7R/8 does not participate in reaction
D. Effectiveness factor for a zero order reaction cannot be 7/8 as it must always be 1