\[a_{1} = 3;\ \ a_{n + 1} = a_{n} - 2\]
\[d = - 2:\]
\[a_{5} = a_{1} + 4d = 3 + 4 \cdot ( - 2) =\]
\[= 3 - 8 = - 5.\]
\[Ответ:4).\]