بررسی گزینه‌ها: 1) $a\left| b \right.\Rightarrow a\left| {{b}^{n}} \right.,{{b}^{n}}\left| c \right.\to a\left| c \right.$ 2) ${{b}^{n}}\left| c \right.\Rightarrow b\left| c \right.$ 3) $a\left| b \right.\Rightarrow {{a}^{n}}\left| {{b}^{n}},{{b}^{n}}\left| c\Rightarrow {{a}^{n}}\left| c \right. \right. \right.$ 4) $a\left| b \right.\Rightarrow \left| a \right|\le \left| b \right|$ پس گزینه‌ی (4) نادرست است.