Medical specialty classification: “Radiology : Pathology : Cardiology” — pick the term that continues the same medical-specialty category.

Introduction / Context:
Analogy items often test recognition of professional or academic domains. Radiology, Pathology, and Cardiology are medical specialties. We must add another recognized medical specialty to the set.

Given Data / Assumptions:

• Radiology → imaging-based diagnostics.
• Pathology → study of disease processes.
• Cardiology → heart and circulatory system specialty.

Concept / Approach:
Select the option that is also a medical specialty ending with -ology in the same professional domain. “Hematology” (study of blood and blood disorders) fits perfectly. Biology, Zoology, Geology, and Ecology are broader sciences, not clinical medical specialties.

Step-by-Step Solution:
1) Identify the shared class: clinical medical specialties.2) From options, pick the clinical specialty: Hematology.3) Exclude general or non-medical sciences.

Verification / Alternative check:
Clinical departments in hospitals commonly include Hematology alongside Cardiology, Radiology, and Pathology.

Why Other Options Are Wrong:

• Biology/Zoology/Geology/Ecology: Academic sciences; not clinical medical specialties in the same sense as the stem.

Common Pitfalls:
Assuming all -ology words are medical specialties. Check domain context.

Final Answer:
Hematology