The 42nd Amendment Act, 1976 made several changes to the Constitution of India, including alterations to the Concurrent List. The Concurrent List consists of subjects on which both the central and state governments can make laws.

Option 1: Family Planning - This subject was added to the Concurrent List under the provisions of the 42nd Amendment Act, 1976. Both the central and state governments have the power to make laws on family planning.

Option 2: Forest - This subject was also added to the Concurrent List under the provisions of the 42nd Amendment Act, 1976. The central and state governments have concurrent powers to legislate on forests.

Option 3: Education - This subject was added to the Concurrent List under the provisions of the 42nd Amendment Act, 1976. Both the central and state governments have the power to make laws on education.

Option 4: Railways - This subject was not added to the Concurrent List of the Constitution of India under the provisions of the 42nd Amendment Act, 1976. Railways remains under the exclusive jurisdiction of the central government.

Therefore, the correct answer is option 4 - Railways.