The correct option is D This
Demonstrative pronouns point out the person(s) or thing(s) to which they refer. Here, the demonstrative pronoun refers to a thing, "the laptop". From the given options, 'this' is the appropriate pronoun, as it refers to something (singular) that's near in time or place to the speaker, here it refers to one laptop near the speaker, hence option D is correct. 'Those' refers to things or people that are not close by, they're far in terms of time or place, from the speaker and refer to plural nouns, whereas 'laptop' is singular. Similarly, 'these', which is the plural of 'this' refers to things or people that are close to the speaker, but like 'those', it's used for plural nouns. Hence options A and B are incorrect. 'My' is a possessive pronoun that works as an adjective, it does not demonstrate anything close or far. 'My' declares ownership of a noun, it precedes that noun that it possesses, for example, 'my novel', where 'my' modifies the noun 'novel'. But here the sentence needs a pronoun that points out the laptop, and not declare its possession, hence option C is incorrect.