Which one of the following is a column matrix?
1
\(\left[ {\begin{array}{*{20}{c}} 1&5&7 \end{array}} \right]\)
2
\(\left[ {\begin{array}{*{20}{c}} 1\\ 2\\ 5 \end{array}} \right]\)
3
\(\left[ {\begin{array}{*{20}{c}} 3&{ - 1}&2\\ 5&4&1 \end{array}} \right]\)
4
\(\left[ {\begin{array}{*{20}{c}} 3&1\\ 2&5\\ 4&8 \end{array}} \right]\)