Final answer:
A fossil that can help us understand an organism's activity during its lifetime is a trace fossil.
Step-by-step explanation:
The correct answer is A. Fossils can provide valuable information about an organism's activity during its lifetime. Trace fossils, also known as ichnofossils, are one type of fossil that can help us understand an organism's activity. These fossils are formed by the traces or impressions left by the activities of ancient organisms, such as footprints, burrows, or feeding marks. By studying trace fossils, scientists can make inferences about the behavior and ecology of the organisms that created them.
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