The image is a person's bald head. The person is facing the right and doesn't have a mouth or eyes. The person also doesn't have ears but there is a question mark on the person's head where the ear would be.
This is a Confusion icon. We've made it in iOS style
, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 13,300 icons, all in the same style and quality.