For the Following Statements and Arguments, Choose Which One of the Following

For the following statements and arguments, choose which one of the following statements best describe the evidence:
-Thanks to those of you (2000 of our subscribers!) who participated in our recent survey (January issue) on happiness in marriage-the results showed that people are happy and content in their marriages-especially if they have children and if the mother can stay home or work only part time. (women's magazine)
Conclusion: People are happy and content in their marriages-especially if they have children and if the mother can stay home or work only part time.

A) The sample is not sufficient in size or is not given.
B) The sample is not random.
C) The sample is not representative (or is lacking in breadth) .
D) The sample is sufficient, random, and representative.