Severe deficiency of Vitamin D results in——-.
A. Scurvy
B. Rickets
C. Night Blindness
D. None of these
Long sight defect could be corrected by using ——-lens.
A. Concave
B. Convex
C. Diverging
D. None of these
The gas used in a refrigerator to cool water is———.
A. Nitrogen
B. Carbon
C. Methane
D. Tetrafluoroethene