Which is NOT correct about primary data research design?

Select one:

a$.$

Use multiple indicators rather than a single measure

b$.$

Always conduct comparative assessments in multiple markets

c$.$

Observations of purchasing patterns, other behavior should weigh more heavily that reports or opinions about purchase intention or price sensitivity

d$.$

It is a waste of time for individual companies to develop customized indicators specific to the industry, product market, or business model.