\noindent\textbf{41.} In the decay process ${}^{11}_{6}\mathrm{C} \longrightarrow {}^{11}_{5}\mathrm{B} + \mathrm{x}$, what is $\mathrm{x}$?
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\noindent (1) proton \hfill (2) $\beta^+$ \hfill (3) $\beta^-$ \hfill (4) neutron
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