Explanation:

- Substantive Law:

- Defines rights and duties.

- Deals with the substance of the law.

- Involves legal obligations, rights, and relationships.

- Adjective Law:

- Also known as procedural law.

- Governs how legal processes are conducted.

- Involves the method and procedure for enforcing rights and obligations.

- Both (a) & (b):

- Suggests that the law of evidence can have characteristics of both substantive and adjective law.

- Neither (a) nor (b):

- Implies the law of evidence does not fall into either category.

- Correct Answer: Option 2 - an adjective law.