To make officially valid or consent to.
They are associated with low density.<span />
Answer:
B) The Case Study
Explanation:
The case study is a research method that generally uses qualitative data, collected from real events, to explain, explore or describe current phenomena inserted in their context. It is usually a way of deepening an individual unit. It serves to answer questions that the researcher does not have much control over the phenomenon studied. That's why it so risks because the researcher doesn't have control over the studied object.
