Step 1: Understanding the Concept:
Rabindranath Tagore founded Shantiniketan on the belief that a child learns best when free and close to nature, not confined to closed walls and strict rules.
Step 2: Why option B is correct.
Tagore held classes under trees, encouraged direct contact with plants, seasons, and open sky, and treated nature as a living teacher. This is the core idea behind his "natural environment" model of education.
Step 3: Why the other options are wrong.
Tagore actively opposed rigid, rule-bound classroom discipline, calling it a "cage" for young minds, so option A contradicts his philosophy. An urban setting was not his ideal, since Shantiniketan was deliberately built in a rural, green setting. Digital environment is a modern concept that did not exist in Tagore's time and has no place in his writings.
Final Answer:
Tagore favoured a natural environment for education. This corresponds to option (B).