Which word in the sentence does the adverb clause modify?

Although you cooked one cup of rice, it expanded to three.

a. expanded

b. cooked

c. rice

d. three

In the sentence, the modified adverb clause is letter C: rice

Adverb clauses or phrases are group of words used in shifting or adding meaning of a verb, clause, adjective, or another adverb. These clauses can be used if: firstly, a sentence contains a subject and a predicate. Secondly, when a subordinate conjunction is used and thirdly, if it answer the ‘adverbial questions’ - when, why, when and how. It is also further categorized to time, place, manner, degree, condition, concession and reason