Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Mollusks reproduce sexually. Most species have separate male and female sexes. Gametes are released into the mantle cavity. Fertilization may be internal or external, depending on the species. Fertilized eggs develop into larvae. There may be one or more larval stages. Each one is different from the adult stage. Mollusks have a unique larval form called a trochophore . It is a tiny organism with cilia for swimming. Answer: trochophore

Answer: What is the unique larval form of mollusks called?

Question: Passage: There are no forces of attraction or repulsion between gas particles . Attractive forces are responsible for particles of a real gas condensing together to form a liquid. It is assumed that the particles of an ideal gas have no such attractive forces. The motion of each particle is completely independent of the motion of all other particles. Answer: superscripts

Answer: Which measure indicates the number of electrons in a given sublevel?

Question: Passage: One of the most familiar ocean zones is the intertidal zone. This is the narrow strip along a coastline that is covered by water at high tide and exposed to air at low tide. You can see an example of an intertidal zone in Figure below . There are plenty of nutrients and sunlight in the intertidal zone. Producers here include phytoplankton and algae. Other organisms include barnacles, snails, crabs, and mussels. They must have adaptations for the constantly changing conditions in this zone. Answer: intertidal zone

Answer:
Which ocean zone is the narrow strip along a coastline that is covered by water at high tide and exposed to air at low tide?