A.I. Explanation:

Option 1: "applied-art objects"

Explanation: In the passage, the word 'they' refers to 'applied-art objects' as it is mentioned in the context of how these objects follow basic patterns determined by the laws of physics. The sentence structure indicates that 'they' is used to describe the subject of the previous clause, which is 'applied-art objects.' This aligns with the overall theme of the text, which discusses the characteristics and limitations of these objects.

Option 2: "the laws of physics"

Explanation: 'The laws of physics' is not the correct reference for 'they' because the laws themselves do not follow patterns; rather, they dictate how applied-art objects are formed. The context of the sentence indicates that 'they' refers to objects that are shaped by these laws, not the laws themselves.

Option 3: "containers"

Explanation: 'Containers' is incorrect because the passage discusses applied-art objects in relation to their functional forms, not containers in general. While containers are mentioned, they do not encapsulate the subject referred to by 'they,' which is specifically about the objects shaped by the laws of physics.

Option 4: "the sides of pots"

Explanation: 'The sides of pots' is not the correct reference for 'they' as it does not relate to the main subject of the passage. The text focuses on applied-art objects and their adherence to the laws of physics, making 'the sides of pots' an irrelevant option in this context.