Option 2, Ratna, is not a high yielding variety (HYV) of wheat. High yielding varieties are developed through scientific breeding methods to increase crop productivity. Sonalika (option 1), Kalyan Sona (option 3), and Girija (option 4) are all examples of HYV wheat varieties. These varieties are specifically bred to have characteristics such as disease resistance, shorter growth duration, and increased grain production. They have been selected and recommended by agricultural research institutions and are widely used by farmers to achieve higher yields. Since Ratna is the only option that is not mentioned as a HYV, it is the correct answer.