The correct answer is C) Concepts that sighted children learn through incidental visual observation.
The statement that is an area of special instruction needed by most students with visual impairments is "Concepts that sighted children learn through incidental visual observation."
When we are talking about visual impairment, what we mean is that the student has a problem with his vision. The teacher has to conscious that this type of student might need a special adaptation to learn the lessons and contents of the class. Probably different schools' materials and tools to increase their learning.
Experts consider visual impairment in the following cases: blindness, legal blindness, and low vision.
That is why teachers have to be very aware of children with these cases so they can adapt their teachings and course material for the benefit of all students.