The question asks which of the given places has yielded the earliest Stupa railing. A Stupa is a Buddhist monument that typically contains sacred relics and is an important symbol in Buddhist architecture. The railing, also known as a Vedika, is a decorative element that usually surrounds the Stupa.

Option 1: Sanchi - This place is known for its ancient Buddhist Stupa and is considered one of the oldest stone structures in India. Sanchi Stupa was built during the Mauryan period (3rd century BCE), making it one of the earliest Stupas in India. It is adorned with a stone railing, which could be the earliest Stupa railing being referred to in the question.

Option 2: Bharhut - Bharhut is another important Buddhist site in India, known for its ancient Stupa and Buddhist sculptures. While it has beautiful railings, these may not be the earliest ones as compared to the railings at Sanchi.

Option 3: Amaravati - Amaravati, located in present-day Andhra Pradesh, is famous for its Buddhist Stupa. However, the exact time period and details about the railings at Amaravati are not mentioned in the question.

Option 4: Nagarjunakondas