Which term best describes the efficiency in using for residual vision?

The term that best describes the efficiency in using residual vision is visual efficiency. Visual efficiency encompasses how well an individual can utilize the vision they have left, particularly in functioning in daily life. It takes into account factors such as visual acuity—the sharpness of vision—as well as how effectively a person can use their vision in various contexts.

Visual efficiency is distinct from visual acuity, which strictly refers to the clarity or sharpness of vision measured under standardized conditions. While visual acuity is an important factor, it alone does not convey how effectively that vision is used in real-life situations.

Other options like poor central vision or tunnel vision refer more to specific conditions of vision loss rather than the overall ability to use whatever residual vision a person may have. Thus, visual efficiency is the most comprehensive term that captures the concept of maximizing the use of remaining vision for effective functioning.