True about amplitude of accommodation?

Is about 10 diopters in emmetropic eye REF: A K Khurana 4th edition, page 41, Yanoff 2nd edition, page 283 Amplitude of accommodation: The difference between the dioptric power needed to focus at near point (P) and far point (R) is called amplitude of accommodation (A). Thus A = P - R. (P= dioptric power needed to see clearly at near point, R= dioptric power needed to see clearly at far point) Thus options A is incorrect, Amplitude of accommodation is not the difference of near and far point but power needed for near and far point. As per formula option D is incorrect, spherical aberration has nothing to do with Accommodation The amplitude of accommodation decreases throughout life from 14D at the age of 10 years to 6D at 40 years and almost OD by the age of 60 years Table 204-2 Accommodative amplitudes at given ages