In “the seafarer” the phrase “summer’s sentinel,” meaning a cuckoo, is an example of
a. a kenning.
c. a scop.
b. a predicate.
d. an exile.

The correct answer is letter a. a kenning. In “The Seafarer” the phrase “summer’s sentinel,” meaning a cuckoo, is an example of kenning. Kenning is a type of circumlocution. It is in the form of a compound that employs figurative language in place of a more concrete single-word noun. 

Ithink it's a, but i might be wrong