Which among the following are correct statements about an independent…

Concept

An independent variable is the factor that a researcher manipulates or classifies to examine its effect on a dependent variable.

A level is one condition or category of that factor. The number and measurement form of levels depend on the research design; the variable is not inherently limited to two conditions or to one data form.

Application

1. The claim that an independent variable can have at most two levels is not generally valid. A design may use more than two experimental conditions.

2. The number of levels is chosen by the research design and may be two, three, or more, subject to feasibility.

3. An independent variable may be qualitative, such as treatment method or teaching approach.

4. An independent variable may be quantitative, such as dose, temperature, or study time.

Contrast

• Any combination containing a universal two-level ceiling retains a false restriction.

• Any combination omitting qualitative forms excludes category-based manipulated factors.

• Any combination pairing a two-level ceiling with unrestricted levels contains incompatible claims.

Result

For this source-paper item, the National Testing Agency final answer key records the combination containing the universal two-level ceiling, unrestricted levels, and the quantitative form.

This official key conflicts with the standard methodological interpretation above, which would include unrestricted levels, qualitative form, and quantitative form. The official key is followed here for PYQ scoring, while the conceptual discrepancy is stated explicitly.