A causal relationship between variables can be demonstrated ...

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A causal relationship between variables can be demonstrated unambiguously by the use of _____.
 
  a. pre-experimental methods c. the experimental method
  b. a valid and reliable survey instrument d. a series of case studies

Question 2

Which method of knowing is used in the following example? An individual accepts as true that black holes exist because 10 physics Nobel laureates assert such is the case.
 
  a. Method of Authority c. Scientific Method
  b. Method of Intuition d. Rationalism

[irishcancer18]

Answer to Question 1

C
Only the use of the experimental method allows for valid causal conclusions.

Answer to Question 2

A

[bb]

Great answer, keep it coming

[cpetit11]

TYSM