Answer:
B. is the answer.
Step-by-step explanation:
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In this case, since the law of conservation of mass states that matter cannot be created nor destroyed, we infer that the correct answer must have the same number of atoms at both sides of the equation.
Therefore, we can see how B. has three white molecules as well as three black molecules at the reactants side and after the chemical reaction there are two molecules having a total of three of each molecule at the products side unlike the other choices; for that reason the correct answer is B.
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