If the signal \({\rm{x}}\left( {\rm{t}} \right) = \frac{{{\rm{sin}}\left( {\rm{t}} \right)}}{{{\rm{\pi t}}}}{\rm{\;*}}\frac{{{\rm{sin}}\left( {\rm{t}} \right)}}{{{\rm{\pi t}}}}\) with ∗ denoting the convolution operation, then x(t) is equal to

• A. \(\frac{{{\rm{sin}}\left( {\rm{t}} \right)}}{{{\rm{\pi t}}}}\)
• B. \(\frac{{{\rm{sin}}\left( {2{\rm{t}}} \right)}}{{2{\rm{\pi t}}}}\)
• C. \(\frac{{2{\rm{sin}}\left( {\rm{t}} \right)}}{{{\rm{\pi t}}}}\)
• D. \({\left( {\frac{{{\rm{sin}}\left( {\rm{t}} \right)}}{{{\rm{\pi t}}}}} \right)^2}\)