Which one of the following is not an area of seismic activity?

Seismic activity is primarily concentrated along tectonic plate boundaries. The three major global seismic belts are the Circum-Pacific Belt (Ring of Fire), the Alpide Belt (Mediterranean-Himalayan), and the Mid-Atlantic Ridge [5]. The Circum-Pacific Belt is the most active, accounting for approximately 70-81% of the world's largest earthquakes [5]. The Mid-Atlantic Ridge is a prominent divergent boundary where seafloor spreading occurs, leading to frequent seismic events. While the Indian Ocean has seismic activity along its mid-oceanic ridges (often grouped within the global ridge system), the term 'Circum-Atlantic Ocean' does not represent a recognized continuous seismic belt. Unlike the Pacific, which is encircled by subduction zones (the Ring of Fire), the Atlantic margins are largely passive, with seismic activity restricted to the central ridge rather than the entire oceanic circumference [5].

Sources

1. [2] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 3: Volcanism and Earthquakes > THE DISTRIBUTION OF EARTHQUAKES > p. 34
2. [5] https://pubs.usgs.gov/gip/dynamic/understanding.html
3. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 11: Volcanism > 11.8. Distribution of Earthquakes and Volcanoes across the World > p. 154