Find the Laplace transform of e-at sin t u(t).

• A. ( frac{s+a}{(s+a)^2- ^2} )
• B. ( frac{ }{(s+a)^2- ^2} )
• C. ( frac{s+a}{(s+a)^2+ ^2} )
• D. ( frac{ }{(s+a)^2+ ^2} )