The eigenvectors of the matrix \(\left[ {\begin{array}{*{20}{c}} 1&2\\ 0&2 \end{array}} \right]\) are written in the form \(\left[ {\begin{array}{*{20}{c}} 1\\ a \end{array}} \right]and\left[ {\begin{array}{*{20}{c}} 1\\ b \end{array}} \right]\). What is a + b ?

• A. 0
• B. ½
• C. 1
• D. 2