Which of the following features might a diamond graded as SI include?

A diamond graded as SI (Slightly Included) typically includes features that are visible under magnification but not necessarily to the naked eye. However, there can be instances where aspects of the inclusions might be visible without magnification, particularly in lower SI grades.

Focusing on the clarity level, SI diamonds often exhibit minor inclusions or blemishes that may be perceived only with careful observation rather than immediate visibility. Therefore, the presence of unnoticeable blemishes aligns correctly with the characteristics of an SI grade, indicating that while the diamond may have some imperfections, they typically do not detract significantly from its overall appearance when viewed without the aid of magnification.

In contrast, visible inclusions to the naked eye, multiple feathers, and notable surface scratches would imply more significant issues that would usually place the diamond in a lower clarity grade than SI. These characteristics are more pronounced and would likely be seen with the naked eye, either on the surface or within the stone, thus making them not representative of the SI grading standard.