Observe the given picture and answer the following questions ?

Which among the following  cannot act as inducers for lac operon ?

Glucose  Galactose Lactose  Both 1 and 2

Both 1 and 2

Remember, glucose or galactose cannot act as inducers for lac operon. Lactose is the substrate for the enzyme beta-galactosidase and it regulates switching on and off of the operon. Hence, it is termed as inducer.