The correct option is C brown spots encompassed by chlorotic veins
The onset of manganese toxicity can be observed via appearance of prominents symptoms like brown spots and chlorotic (yellow appearance due to insufficient chlorophyll) veins in the leaves.
Delay in flowering is a collective symptom for deficiency of nitrogen, sulphur, molybdenum.
Necrosis that is the death of tissues such as leaf tissue is observed as a symptom in case of deficiency of calcium, magnesium, copper, potassium.