Answer: c) increase
Step-by-step explanation:
As the sample size increases it comes closer to the population size, and so converge to a better result of researcher's analysis.
It means the size of the sample is proportional to the power of their statistical tests.
∴ As the size of the sample increases the power of statistical test increases.
Hence, If a research team increases the sample size for a study, the power of their statistical tests will increases.
Therefore , the correct answer is : c) increase
