Extent of a reaction denotes
(a) Total number of moles reacting in a reaction
(b) How much a reaction is occurring?
(c) Number of moles of a reactant that react in a reaction
(d) None of the mentioned
I have been asked this question at a job interview.
This key question is from Terminology for a Reaction System-I in portion Material Balances without Reaction and Material Balances Involving Reactions of Chemical Process Calculation