Examine the following chemical equation, which shows only the reactions and one product. $Zn + 2HCl - ZnCl_2 + ?$ How many H atoms must be present in the second product that is formed?

Question

$\begin{array}{1 1} (a)\;2 \\ (b)\;3 \\ (c)\;4 \\ (d)\;1 \end{array} $