Which of the following statements regarding enzyme inhibition is correct? 
(a) Competitive inhibition is seen when a substrate competes with an enzyme for binding to an inhibitor protein
(b) Competitive inhibition is seen when the substrate and the inhibitor compete for the active site on the enzyme
(c) Non-competitive inhibition of an enzyme can be overcome by adding large amount of substrate
(d) Non-competitive inhibitors often bind to the enzyme irreversibly
(b) A competitive inhibitor competes with substrate molecule for occupying the active site of an enzyme. These inhibitors have structural resemblance with substrate molecules due to which they easily get active site of an enzyme and form an enzyme-inhibitor complex.
E + I EI complex