Well, this is very simple. the cultural background of the individual will affect his choice of the vocabulary to be used. For example, an individual who studied in a French school or in a French-speaking university will use code-switching to French when talking in his native language. An Arabic individual who is panarabist will use code-switching to Modern Standard Arabic when talking in his native Arabic dialect. Having such a cultural background is unfortunately related to the socioeconomic situation of the individual. In fact, a wealthy person can teach his son in a French school. However, a poor person will be obliged to listen the bad language of the street and consequently will spontaneously use it.

thank you for sharing your ideas.:)

This is an incredibly broad question as there are decades worth of studies in sociolinguistics that use socioeconomic class as an independent variable. That also doesn't mean that this variable has been studied so thoroughly that we now have short, simple, reliable answer, quite the contrary in fact, because variation is highly contextual. What Labov (1966) found in his classic study of the Lower East Side was not a universal relationship between socioeconomic class and language variation, but was a relationship between socioeconomic class and language variation in the Lower East Side. If studying a different group, one might very well end up at seeing a different relationship between socioeconomic class and language variation, likewise if one is studying different linguistic variables (Labov studied phonological variables, namely the vowel system and syllable-final (r), but what about a lexical variable like subject pronouns in Montreal French as studied by Sankoff & Laberge (1978)?).

So, initially a lot of results showed that lower middle class speakers tended to lead sound changes, but there is little reason to accept that on any sort of universal level, so the best thing to say here really is that socioeconomic status is often statistically associated with the realization of linguistic variables, one way or another.

the concept of prestige in sociolinguistics is associated with the linguistic variations used by the speakers of a language or languages. they are the most correct , standard or superior variety. there is a usual tendency for people of higher socio economical status to use the prestigious variations of languages or dialects. using prestigious/non-prestigious language, therefore, can represent their socio-economic status. best