Regarding the Stages of and Procedures for Conducting a Survey

Regarding the stages of and procedures for conducting a survey,

A) the purpose of pretesting is to check for associations among variables to see if a larger study is worth doing.
B) one purpose of a cover letter is to deceive respondents so they won't become preoccupied with figuring out the true purpose of the survey.
C) the goal of standardized interviewing is to eliminate the interviewer as a source of measurement error.
D) follow-up efforts seldom are made because of their negligible effects on response rates.