Which of the following statements is correct?

a. Quality of data is key to the success of any analytical exercise since it has a direct and measurable impact on the quality of the analytical model and hence its economic value.

b. Data pre-processing activities such as handling missing values, duplicate data, or outliers are preventive measures for dealing with data quality issues.

c. Data owners are the data quality experts who are in charge of assessing data quality by performing extensive and regular data quality checks.

d. Data stewards can request data scientists to check or complete the value of a field.