Given a scientific passage and an answer, generate a question for the given answer.

Ex Input:
Passage: rates The rates at which reactants are consumed and products are formed during chemical reactions vary greatly. We can identify five factors that affect the rates of chemical reactions: the chemical nature of the reacting substances, the state of subdivision (one large lump versus many small particles) of the reactants, the temperature of the reactants, the concentration of the reactants, and the presence of a catalyst. Answer: catalyst

Ex Output:
The presence of what, which acts as a trigger, affects the rate of chemical reaction?

Ex Input:
Passage: Mouth Brooding. Some species of fish carry their fertilized eggs in their mouth until they hatch. This is called mouth brooding. If you look closely, you can see the eggs inside the mouth of the cardinalfish pictured here. Answer: mouth brooding

Ex Output:
Some species of fish carry their fertilized eggs in their mouth until they hatch; this is called what?

Ex Input:
Passage: What happens when forces of evolution work over a long period of time? The answer is macroevolution. An example is the evolution of a new species. Answer: macroevolution

Ex Output:
What happens when forces of evolution work over a long period of time?