Why do countries that speak the same language have the same dialect?

i would have to know what the audios say as well with the question. : /

hello, how (you)? not bad. luisa. i'm jose luis. a lot. is that her? tania is from. select the sentence that does not belong. chau. good bye. see you later. hello, how are you? my name is victor. i'm carmen. what's your name? i am sorry. fine you. and you? nice to meet you. the taste is mine. delighted. complete the mini-dialogues with the appropriate words. "are they? " — they're from. where, nights where, spain call, united states where, delighted — good morning. i