Instructions: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Input: Passage: As the musical prelude climaxes, Woglinde and Wellgunde are seen at play in the depths of the Rhine. Flosshilde joins them after a gentle reminder of their responsibilities as guardians of the gold. They are observed by the Nibelung dwarf Alberich who calls out to them: "I'd like to draw near if you would be kind to me". The wary Flosshilde cries: "Guard the gold! Father warned us of such a foe". When Alberich begins his rough wooing the maidens relax: "Now I laugh at my fears, our enemy is in love", says Flosshilde, and a cruel teasing game ensues. First, Woglinde pretends to respond to the dwarf's advances but swims away as he tries to embrace her. Then Wellgunde takes over, and Alberich's hopes rise until her sharp retort: "Ugh, you hairy hunchbacked clown!" Flosshilde pretends to chastise her sisters for their cruelty and feigns her own courtship, by which Alberich is quite taken in until she suddenly tears away to join the others in a mocking song. Tormented with lust, Alberich furiously chases the maidens over the rocks, slipping and sliding as they elude him, before he sinks down in impotent rage. At this point the mood changes: as a sudden brightness penetrates the depths, a magical golden light reveals, for the first time, the Rhinegold on its rock. The maidens sing their ecstatic greeting to the gold, which rouses Alberich's curiosity. In response to his question Woglinde and Wellgunde reveal the gold's secret: measureless power would belong to the one who could forge a ring from it. Flosshilde scolds them for giving this secret away, but her concerns are dismissed—only someone who has forsworn love can obtain the gold, and Alberich is clearly so besotted as to present no danger. But their confidence is misplaced; in his humiliation Alberich decides that world mastery is more desirable than love. As the maidens continue to jeer his antics he scrambles up the rock and, uttering a curse on love, seizes the gold and disappears, leaving the Rhinemaidens to dive after him  bewailing their loss.
Output:
What are the names of the three people who are observed by the Nibelung dwarf Alberich?