Given sets $A = \{ x \mid x - 1 \geqslant 0 \} , B = \{ 0,1,2 \}$, then $A \cap B =$\\ A. $\{ 0 \}$\\ B. $\{ 1 \}$\\ C. $\{ 1,2 \}$\\ D. $\{ 0,1,2 \}$