Acomplete subject includes the simple subject plus a
a. verb
b. predicate
c. singular noun
d. modifier
it was d.

D) modifier.

Explanation: The subject in a sentence is the person or thing that performs the action of the verb. A simple subject is the main noun (person, place, thing, or idea) that performs the action. A complete subject is formed by the simple subject plus one or more modifiers, that are words (especially an adjectives nouns) used attributively, that restricts or adds to the sense of a head noun. So the correct answer is option  D.

the anwser is went creeping down the river again, across the wide lonely marshes to the sea.

i longed to go with them out into the world to seek my fortune in foreign lands—africa, india, china and peru!

and, dreaming of the lands i had never seen, i'd sit on there, watching till they were out of sight.

the correct answer would b,   to show that she was very influential in the democratic party.