Please choose the correct answer to the question: The incompleteness of the fossil record results primarily from which phenomenon?

Answer1: the frequency and irregular timing of organism speciations Answer2: the metamorphosis of most sedimentary rock by heat and pressure Answer3: the geologically rapid cycling of crust material back into the mantle Answer4: the rarity with which organic remains are exposed to fossil-forming conditions

Answer format: answer1/answer2/answer3/answer4
Answer: answer4