Find the odd geography item (island vs country): Identify the option that is not a single island but a sovereign country spanning mainland and islands.

Introduction / Context:
Geographic odd-one-out problems frequently rely on type distinctions such as island vs mainland, or country vs island. Three items here are islands (one of which is an island country), while one is a sovereign nation that includes both mainland territory and islands, and is not itself a single island.

Given Data / Assumptions:

• Java: a major Indonesian island.
• Tasmania: an island state of Australia.
• Sri Lanka: an island nation (sovereign country) that is itself a single main island with smaller islets.
• Malaysia: a sovereign country with territories on the Malay Peninsula (mainland) and on the island of Borneo (Sabah and Sarawak), i.e., not a single island.

Concept / Approach:
Classify by “single island” vs “country with mainland and island components.” Java and Tasmania are islands; Sri Lanka is an island country centered on one main island. Malaysia, however, is a multinational-type polity in geographic form—partly mainland (Peninsular Malaysia) and partly on Borneo—thus not a single island.

Step-by-Step Solution:

Verification / Alternative check:
Consider political geography: Java and Tasmania are subnational island units; Sri Lanka is a country but a single primary island. Malaysia’s territory crosses mainland and island blocks, uniquely differentiating it.

Why Other Options Are Wrong:
They are islands (or an island nation), which form a coherent class distinct from a country comprising both mainland and island territories.

Common Pitfalls:
Do not assume every country named must be an island country; verify territorial composition. Malaysia is not an island and cannot be categorized as one.

Final Answer:
Malaysia