Answer:
The best synonym for validity is C. Truthfulness.
Step-by-step explanation:
The best synonym for validity is C. Truthfulness.
Validity refers to the degree to which a measure or research design accurately measures or reflects the concept or phenomenon being studied. In other words, a study is considered valid if it measures what it is intended to measure and if the results accurately represent the phenomenon being studied. Truthfulness also refers to the accuracy and reliability of information or data, making it the most appropriate synonym for validity.
The other options are not accurate synonyms for validity. Consistency refers to the reliability and repeatability of results, feasibility refers to the practicality or likelihood of success, and economy refers to efficiency and cost-effectiveness.