Which term means a limitation or restriction?

• A. Independent variable
• B. Constraint
• C. Ecosystem
• D. Trend

Answer: (B)

The main idea tested here is identifying a word that describes a limitation or restriction. A constraint is exactly that: something that limits what can be done, how an experiment is designed, or what outcomes are possible. Constraints shape how you approach a task by setting boundaries like time, budget, available materials, or specific conditions you must work within. For example, if you’re studying how a plant grows but you only have two weeks to observe it, that time limit is a constraint on your investigation.

In contrast, an independent variable is what you deliberately change to see its effect, not a restriction. An ecosystem refers to the living organisms and their environment, a broader system rather than a limiting factor. A trend is a general direction in data over time, describing a pattern rather than a boundary.

So the term that means a limitation or restriction is constraint.