If \[\text{l}_{r}^{2}+m_{r}^{2}+n_{r}^{2}=\text{1};\] \[r=1,2,3\] and \[{{\text{l}}_{r}}{{\text{l}}_{s}}+{{m}_{r}}{{m}_{s}}+{{n}_{r}}{{n}_{s}}=0;\]\[r\ne s,\]\[r=1,2,3;\] \[s=1,2,3,\]then the value of \[\left| \begin{matrix} {{\text{l}}_{1}} & {{m}_{1}} & {{n}_{1}} \\ {{\text{l}}_{2}} & {{m}_{2}} & {{n}_{2}} \\ {{\text{l}}_{3}} & {{m}_{3}} & {{n}_{3}} \\ \end{matrix} \right|\] is

• A. \[0\]
• B. \[\pm 1\]
• C. \[2\]
• D. None of these