*Question*
Q: The conducting zone of the respiratory system includes the organs and structures not directly involved in what?   Read this paragraph and choose the correct option from the provided answers:  Functionally, the respiratory system can be divided into a conducting zone and a respiratory zone. The conducting zone of the respiratory system includes the organs and structures not directly involved in gas exchange. The gas exchange occurs in the respiratory zone.   Choices:  - copper exchange  - helium exchange  - gold exchange  - gas exchange   A:
**Answer**
gas exchange

*Question*
Q: As lava cools, tiny iron-rich crystals line up with earth’s what?   Read this paragraph and choose the correct option from the provided answers:  Some rocks contain little compasses too! As lava cools, tiny iron-rich crystals line up with Earth’s magnetic field. Anywhere lavas have cooled, these magnetite crystals point to the magnetic poles. The little magnets point to where the north pole was when the lava cooled. Scientists can use this to figure out where the continents were at that time. This evidence clearly shows that the continents have moved.   Choices:  - gravitational field  - oceans  - molecular field  - magnetic field   A:
**Answer**
magnetic field

*Question*
Q: How many chambers are in a reptiles heart?   Read this paragraph and choose the correct option from the provided answers:  Reptiles are a class of ectothermic, tetrapod vertebrates. They have several adaptations for living on dry land, such as tough keratin scales and efficient lungs for breathing air. They also have a three-chambered heart and relatively well-developed brain.   Choices:  - ten  - two  - five  - three   A:
**Answer**
three

*Question*
Q: What is the smallest aromatic hydrocarbon?   Read this paragraph and choose the correct option from the provided answers:  Unsaturated hydrocarbons called aromatic hydrocarbons are cyclic hydrocarbons that have double bonds. These compounds have six carbon atoms in a ring with alternating single and double bonds. The smallest aromatic hydrocarbon is benzene, which has just one ring. Its structural formula is shown in the Figure below . Larger aromatic hydrocarbons consist of two or more rings, which are joined together by bonds between their carbon atoms. The name of aromatic hydrocarbons comes from their strong aroma, or scent. That’s why they are used in air fresheners and mothballs. You can learn more about these interesting hydrocarbons at this URL:.   Choices:  - furan  - sulfide  - phosphate  - benzene   A:
**Answer**

benzene