Based on the description of this experiment, it can be inferred the process of data collection is flawed (last option).
This experiment focuses on understanding energy exchange between colliding objects.
In this experiment conditions such as the materials and the conditions were constant. This makes the experiment effective.
Moreover, considering energy is regulated by laws that have been proven by scientists multiple times before it is expected that under the same conditions the results are similar if not identical.
It is likely students are not recording the results or data effectively and due to this, the results are different.
Learn more about experiments in: https://brainly.com/question/11256472
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