Final answer:
The comparison 'The chord hummed and swung like a swallow's note' is a a) simile because it uses the word 'like' to compare the sound of a chord to the sound made by a swallow.
Step-by-step explanation:
The literary term for the comparison "The chord hummed and swung like a swallow's note" is a simile. A simile is a figurative tool used to make a comparison between two unlike things by employing the words 'like' or 'as'. This device creates an imagery that helps the reader to visualize or understand the object of comparison better by relating it to something more familiar. In the case of the provided comparison, the sound of a chord is compared to the sound a swallow makes, emphasizing the melodic and fluid quality of the chord through the use of 'like'.