The underlined phrase "excited about the sale" has the following function among the ones provided:
4. It acts as an adjective because it describes the noun "group."
The phrase "excited about the sale" consists of a participle and its complements, which makes it a participial phrase. This type of phrase functions as an adjective, which means it modifies a noun in the sentence.
In this case, the noun being modified is "group". The phrase is providing additional information about the group of shoppers that arrived early.
Learn more about participial phrases here:
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