You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Q: The incompleteness of the fossil record results primarily from which phenomenon?  
 (A) the frequency and irregular timing of organism speciations (B) the metamorphosis of most sedimentary rock by heat and pressure (C) the geologically rapid cycling of crust material back into the mantle (D) the rarity with which organic remains are exposed to fossil-forming conditions

A: D
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Q: Which of these will best separate a saltwater solution?  
 (A) using a paper filtering system (B) using chromatography (C) allowing the salt to settle (D) allowing the water to evaporate

A: D
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Q: When a volcano erupts, new lava is deposited on the slopes of the volcano. After the lava cools and hardens, which types of organisms will most likely be the first to live on the new material?  
 (A) large reptiles and amphibians (B) small birds and mammals (C) mosses and lichens (D) bushes and vines

A:
C
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