Final answer:
Stanley Miller and Harold Urey's model demonstrated that organic precursors could have assembled into complex molecules necessary for life.
Step-by-step explanation:
Stanley Miller and Harold Urey's model supported the claim that organic precursors present on early Earth could have assembled into large, complex molecules necessary for life. Their famous Miller-Urey experiment simulated the conditions of Earth's early atmosphere by providing energy to a mixture of inorganic molecules with reducing power. The resulting reactions yielded organic molecules, including amino acids, the building blocks of proteins.