Solution:
Concept: In reversible reactions forward and backward reactions take place simultaneously and in a reversible reaction, reactants form products and these products can go back to the original state.A + B ⇋ C + D
After some time, an equilibrium is reached. At this stage, the rate of forwarding reaction will be equal to backward reaction. It does not mean the reaction is stopped. The reaction continues here also.
Since the products are reverting to reactants, the reaction does not complete. After equilibrium, the reaction rate will be constant.
Even after the removal of reactants, the products convert into reactants and a new equilibrium is attained. Thus the correct answer is they never proceed to completion.
Hence, the correct answer is option 1.