Final answer:
Informal language is relaxed, casual language used to communicate personal content with a familiar audience. It includes jargon and slang.
Step-by-step explanation:
Informal language is language best used to communicate more personal, subjective content with an audience you know fairly well. It is a relaxed and casual form of communication that is used in informal settings.
Informal language is not strictly limited to use with only your best friend (option C), nor is it limited to a specific style of clothing (option B). It includes jargon and slang, which are informal terms and expressions that are specific to certain groups or communities.
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