A person with short-sightedness or myopia cannot see objects clearly beyond $$2.5\,\mathrm{m}$$. The power of lens required to correct his vision is

A

$$+2.5\,\mathrm{D}$$

B

$$+0.4\,\mathrm{D}$$

C

$$-2.5\,\mathrm{D}$$

D

$$-0.4\,\mathrm{D}$$