Answer: Eighth note
Step-by-step explanation:
Each of the notes are what they are called of a four-beat - for example, a quarter note is one quarter of a 4/4 measure, therefore it has one beat. A half note has two beats, and a whole note holds four beats. An eighth note is half of a quarter note (1/8 is half of 1/4) so it holds half a beat. Therefore, an eighth note is the shortest.
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