Explanation:

- Statement (A): After the Nagpur Session of the Indian National Congress in 1920, the provincial Congress Committees were indeed reorganized on a linguistic basis. This was to make the organization more accessible and effective among the local populations.

- Statement (B): In 1948, the Indian National Congress rejected the demand to form provinces based on linguistic lines. This stance was reflected in the Congress's position during the discussions on state reorganization post-independence.

- The correct answer is indeed Option 4: Both (A) & (B). Both statements provided are accurate regarding historical events related to the Indian National Congress and linguistic organization.