Answer:
Assonance.
Step-by-step explanation:
Assonance is a literary device that refers to the repetition of the vowel sounds in a line of poetry. In other words, it also refers to the repetition of the vowel sounds but not the consonant sounds, in close proximity.
The given line of poetry from John Masefield's "Sea Fever" uses the sound device of assonance. This is found in the repetition of the /i/ and /e/ sounds in the given line.
Thus, the correct answer is assonance.