Which of the following correctly defines amblyopia?

a) Programmed cell death that is a regular part of development.
b) A decrease in vision in one eye.
c) A generally fatal failure of the rostral part of the neural plate to fuse.
d) A misalignment of the eyes in which one or both eyes deviates towards the nose.
e) A condition where the structure of the eye fails to develop completely.

Answer: B