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

Ex Input:
Passage: The stoichiometry of a reaction describes the relative amounts of reactants and products in a balanced chemical equation. A stoichiometric quantity of a reactant is the amount necessary to react completely with the other reactant(s). If a quantity of a reactant remains unconsumed after complete reaction has occurred, it is in excess. The reactant that is consumed first and limits the amount of product(s) that can be obtained is the limiting reactant. To identify the limiting reactant, calculate the number of moles of each reactant present and compare this ratio to the mole ratio of the reactants in the balanced chemical equation. The maximum amount of product(s) that can be obtained in a reaction from a given amount of reactant(s) is the theoretical yield of the reaction. The actual yieldis the amount of product(s) actually obtained in the reaction; it cannot exceed the theoretical yield. The percent yield of a reaction is the ratio of the actual yield to the theoretical yield, expressed as a percentage. Answer: in excess

Ex Output:
If a quantity of a reactant remains unconsumed after complete reaction has occurred, it is?

Ex Input:
Passage: Biotechnology has been used to create transgenic crops. Transgenic crops are genetically modified with new genes that code for traits useful to humans. The diagram in Figure below shows how a transgenic crop is created. You can learn more about how scientists create transgenic crops with the interactive animation "Engineer a Crop: Transgenic Manipulation" at this link: http://www. pbs. org/wgbh/harvest/engineer/transgen. html . Answer: transgenic

Ex Output:
What is the term for crops that are genetically modified with new genes that code for traits useful to humans?

Ex Input:
Passage: Penguins are flightless birds that are strong swimmers and spend much of their time in the water. Answer: penguins

Ex Output:
What are flightless birds that are strong swimmers and spend much of their time in the water?