$f:N\to A$ where A = {0,1} defined by $f\left(x\right)=\left\{\begin{array}{l}0\text{\hspace{0.33em}}ifxisodd\\ 1ifxiseven\end{array}\right..$ Then f is

• A

  one-one, onto

• B

  one-one, into

• C

  many-one, onto

• D

  many-one, into