Assertion: The main roads which are constructed and maintained by the Central Government are known as the National Highways.
Reasoning: These roads are meant for intra-state transport and movement of defence men and material in strategic areas.

Assertion (A) is true but Reasoning (R) is not correct.

The correct answer is: Option 3: Assertion (A) is true but Reasoning (R) is not correct.

Assertion (A) is correct: As stated before, National Highways are indeed the main roads constructed and maintained by the Central Government of India.

Reasoning (R) is incorrect: National Highways are primarily meant for inter-state transport, not intra-state transport. They connect different states and major cities across the country, facilitating movement of goods and people over longer distances. While National Highways can be used for intra-state travel as well, that's not their main purpose.

NCERT Text: The main roads which are constructed and maintained by the Central Government are known as the National Highways. These roads are meant for inter-state transport and movement of defence men and material in strategic areas. These also connect the state capitals, major cities, important ports, railway junctions, etc.