কোনটি y- অক্ষের উপর লম্ব হবে?

$(\hat{\mathrm{i}} \times \hat{\mathrm{j}}) \times \hat{\mathrm{i}}$

$(\hat{\mathrm{i}} \times \hat{\mathrm{j}}) \times \hat{\mathrm{k}}$

$(\hat{\mathrm{j}} \times \hat{\mathrm{i}}) \times \hat{\mathrm{j}}$

$(\hat{\mathrm{k}} \times \hat{\mathrm{j}}) \times \hat{\mathrm{k}}$