Cho phương trình đường thẳng \(\left( \Delta \right):\,\,2x-y+1=0.\,\,{{T}_{\overrightarrow{u}}}\left( \Delta \right)\mapsto \Delta ,\,\,\overrightarrow{u}\)là :
A. \(\left( 2;-1 \right)\)
B. \(\left( 1;2 \right)\)
C.\(\left( -1;2 \right)\)
D.\(\left( 2;2 \right)\)