Step 1: Analyzing the options.
- Idealism (A) is associated with thinkers like F.H. Bradley, who is known for his idealist philosophy, so it matches with IV.
- Rationalism (B), associated with D. Hume, is focused on reason as the path to knowledge, so it matches with II.
- Empiricism (C), which emphasizes knowledge coming from sensory experience, is associated with B. Spinoza, so it matches with III.
- Pragmatism (D) is linked to C.S. Peirce, who is considered one of the founders of pragmatism, so it matches with I.
Step 2: Conclusion.
The correct answer is Option 2.
Final Answer:
\[
\boxed{\text{The correct answer is 2. A - I, B - II, C - III, D - IV.}}
\]