The Correct Answer and Explanation is:
The correct answer is observes.
The scientific method is a structured approach to investigation and discovery that forms the backbone of scientific inquiry. The question asks to identify the key action performed during experimentation to understand what is happening. The most accurate answer is “observes” because observation is the primary method of data collection while an experiment is underway.
During the experimental phase, a scientist is actively testing a hypothesis. To do this, they must carefully monitor the process and record all relevant information. This act of monitoring and recording is observation. Observations can be qualitative, involving descriptions based on the senses, such as noticing a change in color, texture, or the release of an odor. They can also be quantitative, involving the use of instruments to take precise measurements, like recording temperature, pressure, length, or time. This collection of raw data is the evidence upon which the entire scientific conclusion will rest. Without careful observation, the experiment would yield no useful information.
The other options represent different stages of the scientific method. A scientist “predicts” when they formulate a hypothesis, which is a testable prediction made before the experiment begins. One “plans” the experiment by designing the procedure, controlling variables, and gathering materials, all of which also happen before the experiment starts. Finally, a scientist “concludes” after the experiment is complete. This step involves analyzing the data gathered through observation and interpreting the results to determine whether the hypothesis was supported or refuted. Therefore, observing is the unique and critical activity that occurs throughout the experimental process itself.
