Read the following passage and answer the question:
It is important to recognize and to celebrate the wide range of cultures that exist. Of late differences of opinion has cropped concerning multiculturalism. The multiculturalists argue that we must recognize cultural differences that are legitimately linked to language and religion. In multiculturalism, minority groups see opportunities to play a part in moulding the national culture even as they are molded by it. Campus multiculturalism, variations among students, have tried with some success to talk about how a racially and ethnically diverse student body can enrich everyone's education. For these multiculturalists, differences are absolute, irreducible, and intractable. The hardliners are not interested to allow Americans to belong to more than a single culture, to be both particularisms and Universalists. The time-honored India mixture of assimilation and traditional allegiance is denounced as a danger to racial and gender authenticity. The multiculturalists insist on seeing all perspectives as tainted by the perceiver's particular point of view. Impartial knowledge, they argue, is not possible, because ideas are simply the expression of individual identity that are linked to culture or a language.
The provided passage discusses the concept of multiculturalism and the arguments surrounding it. A key point raised is what constitutes the basis for recognizing cultural differences within multiculturalism.
According to the passage, the multiculturalists argue that cultural differences are legitimately recognized when they are connected to specific aspects of identity and heritage. The text explicitly states: "The multiculturalists argue that we must recognize cultural differences that are legitimately linked to language and religion."
This statement directly identifies language and religion as the factors that, according to the multiculturalists discussed in the passage, make multiculturalism legitimate. These elements are seen as core components of cultural identity that warrant recognition and celebration.
Therefore, based on the specific argument presented in the passage, language and religion are identified as the key elements that make multiculturalism legitimate.