What is the verb phrase in the sentence?

the sea turtles were walking slowly across the sand.

a.
slowly across

b.
walking slowly

c.
were walking

d.
turtles were

i believe it is d.) previous creature

comfortable

explanation:

one type of the adjectives is predicate adjective. a predicate adjective is an adjective which follows a linking verb and modifies or refers back to the main subject of that linking verb.

it usually is used just before the noun it modies.

here in this example:

'penguins seem comfortable in the coolest habitats', comfortable is the predicate adjective which follows the linking verb 'seem' and modifies the noun.