<h2>Answer:</h2>
Option (B):
The products can form reactants, and the reactants can form products.
<h3>Explanation:</h3><h3>Reversible reaction</h3>
A reversible reaction is a reaction where the reactants form products, which react together to give the reactants back.
aA + bB ⇄ cC + dD
A and B can react to form C and D or, in the reverse reaction, C and D can react to form A and B.
Other options are wrong because off:
(A) Concentration changes with time equilibrium concentration and higher product concentration is also possible.
(C) They may be constant.
(D) Concentration changes with time equilibrium concentration and higher reactant concentration is also possible.