\textbf{229.} Based on the reaction: $\mathrm{A(g) + 3B(g) \rightleftharpoons 2C(g)}$, $K = 6.22\,\mathrm{L^2\cdot mol^{-2}}$, if $0.1$, $0.2$, and $0.3$ mol of substances $\mathrm{A(g)}$, $\mathrm{B(g)}$, and $\mathrm{C(g)}$ respectively are introduced into a one-liter flask, which graph correctly shows the change in their concentrations?
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\textit{[Figure: Four graphs (1)--(4) showing molarity vs. time plots for substances A, B, and C approaching equilibrium]}
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