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

[Q]: Passage: Regulation of transcription in prokaryotes typically involves operons. An operon is a region of DNA that consists of one or more genes that encode the proteins needed for a specific function. The operon also includes a promoter and an operator. The operator is a region of the operon where regulatory proteins bind. It is located near the promoter and helps regulate transcription of the operon genes. Answer: operon
[A]: Which region of dna consists of one or more genes that encode the proteins needed for a specific function?

[Q]: Passage: An ideal gas is one that follows the gas laws at all conditions of temperature and pressure. To do so, the gas would need to completely abide by the kinetic-molecular theory. The gas particles would need to occupy zero volume and they would need to exhibit no attractive forces what so ever toward each other. Since neither of those conditions can be true, there is no such thing as an ideal gas. A real gas is a gas that does not behave according to the assumptions of the kinetic-molecular theory. Fortunately, at the conditions of temperature and pressure that are normally encountered in a laboratory, real gases tend to behave very much like ideal gases. Answer: ideal gas
[A]: What is the term for a gas that completely abides by the kinetic-molecular theory?

[Q]: Passage: Mollusks are probably most closely related to organisms in the phylum Annelida , also known as segmented worms. This phylum includes the earthworm and leech. Scientists believe these two groups are related because, when they are in the early stage of development, they look very similar. Mollusks also share features of their organ systems with segmented worms. Unlike segmented worms, however, mollusks do not have body segmentation. The basic mollusk body shape is usually quite different as well. Answer: segmented worms
[A]:
Mollusks are probably most closely related to organisms in the phylum annelida , also known as what?