Which of the Following Statements Is True in Relation to Research

Which of the following statements is true in relation to research?

A) By searching over and over again, each study should contribute to our understanding of the issue
B) Most research studies will provide definitive answers to the problem examined
C) Often, searching or investigating a topic more than once, may detract from our understanding of the issue
D) Some research studies will not provide definitive answers to the problem, in which case further investigation should be postponed