Final answer:
Option B - 'softly seated on the leaves' is an example of alliteration due to the repetition of the initial 's' consonant sound. Therefore, the correct option is B.
Step-by-step explanation:
The student has asked which phrase from the poem shows an example of alliteration. Alliteration is defined as the repetition of consonant sounds at the beginning of words. After examining the options given, option B - 'softly seated on the leaves' is an example of alliteration because the 's' sound is repeated at the start of 'softly' and 'seated'. This creates a rhythmic effect and can emphasize the imagery or thematic elements of a poem.