Đặt lim un = a, lim vn = b. Mệnh đề nào dưới đây sai?

A. $\lim ({\mathrm{u}}_{\mathrm{n}}.{\mathrm{v}}_{\mathrm{n}})=\lim {\mathrm{u}}_{\mathrm{n}}+\lim {\mathrm{v}}_{\mathrm{n}}.$

B. $\lim ({\mathrm{u}}_{\mathrm{n}}+{\mathrm{v}}_{\mathrm{n}})=\lim {\mathrm{u}}_{\mathrm{n}}+\lim {\mathrm{v}}_{\mathrm{n}}.$

C. $\lim ({\mathrm{u}}_{\mathrm{n}}-{\mathrm{v}}_{\mathrm{n}})=\lim {\mathrm{u}}_{\mathrm{n}}-\lim {\mathrm{v}}_{\mathrm{n}}.$

D. $\lim ({\mathrm{u}}_{\mathrm{n}}.{\mathrm{v}}_{\mathrm{n}})=\lim {\mathrm{u}}_{\mathrm{n}}.\lim {\mathrm{v}}_{\mathrm{n}}.$