Step 1: Understanding the Question
The question asks to identify the specific national body in India that is authorized to assign the International Standard Serial Number (ISSN) to serial publications like journals and magazines.
Step 2: Key Formula or Approach
The approach is to understand the structure of the international ISSN system. It operates through a network of national centers, each responsible for assigning ISSNs in its respective country.
Step 3: Detailed Explanation
The global ISSN system is coordinated by the ISSN International Centre in Paris.
In India, the designated authority is the ISSN National Centre of India.
This centre is located at the National Science Library (NSL), which is part of the CSIR-National Institute of Science Communication and Policy Research (NIScPR) in New Delhi.
While it is housed within the National Science Library, its official name for this function is the "ISSN National Centre of India".
Step 4: Final Answer
The organization officially responsible for assigning ISSNs is the ISSN National Centre of India. Therefore, Option (D) is the most precise and correct answer.