Middle-aged Robert and his adolescent son are sitting at the table reading the newspaper. Robert is holding his section of the newspaper rather far from his eyes. His son asks, "Dad, why are you holding the paper so far away? If I held it that far away, I could not read anything!" Robert replies, "I think it is because I am developing:

a. nearsightedness

d. macular degeneration

c. presbycusis

b. auditory degeneration