Regarding color blindness true:

A i.e., Mainly congenital B i.e., Can be tested by Farnswoh 100 hue test; C i.e. Ishihara cha test red/ green colour blindness Tests for color vision Pseudoisochromatic chas - Ishihara plates mainly to screen congenital protan & deuterans (i.e., red & green defects)Q - Hardy -Rand - Rittler plates is more sensitive to Ishihara since it can defect all three congenital defects Edridge Green lantern test : the subject has to identify various colours shown to him (in lantern) & judgement depends on mistake he makes. City university test : a spectroscopic test where subject is asked to match central colour to its closest hue from 4 peripheral surrounding colour in each of 10 plates. Fanswoh Munsell 100 hue test is the most sensitiveQ for both congenital & aquired colour defects. It consists of 85 hue caps (not 100) and vision is judged by error score i.e., higher score = poorer vision. Fanswoh D 15 hue discrimination test is similar test but utilizes only 15 hue caps Nagel's anomaloscope (asked to mix red & green to make a given shade) Holmgren's wool testQ