The correct answer is option 'D' - Indian Road Congress.

Indian Road Congress (IRC):
- The Indian Road Congress (IRC) is a semiofficial body established in 1934 with the objective of promoting and encouraging the scientific and economic development of roads and bridges in India.
- It is the premier technical body in the field of road transport and highways in the country.
- The IRC works towards the standardization, development, and maintenance of roads and bridges in India.
- It formulates various guidelines, specifications, and codes of practices related to the design, construction, and maintenance of roads and bridges.
- The organization also conducts research and development activities in the field of road engineering and technology.
- The IRC collaborates with various government agencies, research institutes, and industry stakeholders to exchange knowledge and expertise in the field of road and bridge engineering.
- The organization plays a significant role in the planning, design, and construction of roads and bridges across the country.
- It also provides technical advice and assistance to the government and other agencies involved in the development and maintenance of road infrastructure.
- The IRC has various technical committees and expert groups that focus on different aspects of road engineering such as pavement design, bridge design, traffic engineering, etc.
- These committees and groups review and update the existing standards and specifications to keep them in line with the latest advancements in road engineering.
- The organization also conducts training programs, seminars, and conferences to disseminate knowledge and promote best practices in the field of road and bridge engineering.
- The Indian Road Congress has played a crucial role in the development of the road infrastructure in India and continues to contribute towards the improvement and standardization of roads and bridges in the country.