Answer:
Adverb clause.
Step-by-step explanation:
An adverb clause includes the accumulation of words beginning with a subordinate conjunction like "Although", "If", "As", etc. It contains a verb and a subject to add meaning and functions as an adverb in the sentence. The adverb clause italicized here is "Even though Darla recommended the course" as it accommodates all the above features like begins with "Even though"(subordinate conjunction), includes a subject(Darla) and a verb(recommended). Thus, it exemplifies the adverb clause.