I believe it's an Indefinite pronoun. Hope this helps...
C
A
D
B
(in order)
If you take a look into each definition, you will be able to match and make a conclusion.
If the verb in the independent clause is in the present tense, the tense that the verb in the indirect quotation should be is <span>remain in its original tense.
</span>You don't have to shift tenses because it is present in the independent one.
For example:
He says: "I need to wash my hair."
He says that he needs to wash his hair.
You wouldn't say - he says that he needed to wash his hair.
If the italicized sentence is <em>how eager she was to do her best, </em>then the answer would be an adverb clause.
Because the whole clause acts as an adverb.