Final answer:
In scientific research, an Observation is recorded information, a Variable is a changing factor, and a Data Set is a collection of values. These definitions match the terms with the options D, C, and A respectively.
Step-by-step explanation:
To match the following words to their definitions: Observation (Obs), Variable, Data Set, let's look at each term in the context of scientific research:
- Observation (Obs): This is a recorded piece of information, which matches definition D. An observation can be qualitative or quantitative, such as noting the color of a chemical reaction or measuring the temperature during an experiment.
- Variable: This is a factor in an experiment that can change. Researchers often study how variables impact each other. Thus, the correct match is C, a changing factor.
- Data Set: This term refers to a collection of values or observations collected in scientific investigations, which aligns with definition A, a set of values.
With these matches, we can conclude:
- Obs: Recorded information (D).
- Variable: Changing factor (C).
- Data Set: A set of values (A).