Deductive reasoning is the correct answer.

Explanation:

Deductive reasoning is a type of logical thinking where a general principle or theory is applied to specific cases to draw conclusions. It is a top-down approach in which the validity of the conclusion is based on the truth of the general principle. In deductive reasoning, if the general principle is true, the conclusion must also be true.

In the context of the question, when theories or principles are widely accepted and applied to explain particular cases, it refers to the use of deductive reasoning. Here are the reasons why:

1. Widely accepted theories or principles: Deductive reasoning relies on established theories or principles that are widely accepted in a specific field or domain. These theories provide a foundation for reasoning and help to explain various phenomena.

2. Applied to explain particular cases: Deductive reasoning involves applying these theories or principles to specific cases or situations. By using deductive reasoning, one can analyze the given information, identify relevant theories or principles, and draw logical conclusions based on them.

3. Drawing specific conclusions: The goal of deductive reasoning is to draw specific conclusions based on the application of general principles to particular cases. These conclusions are derived from the logical implications of the theories or principles being used.

4. Validating the general principle: If the conclusions drawn through deductive reasoning align with the expected outcomes, it helps to validate the general principle or theory being applied. The more consistent the conclusions are with the established principles, the stronger the evidence becomes for the validity of those principles.

In summary, deductive reasoning is the process of using widely accepted theories or principles to explain specific cases. It allows for the application of general knowledge to draw specific conclusions and helps in validating the principles or theories being used.