Correctly match column-I with column-II.

$\begin{array}{cccc}& \text{Column I}& & \text{Column II}\\ \text{(A)}& \text{Tetany}& \text{(i)}& \text{Auto immune disorder}\\ \text{(B)}& \text{Osteoporosis}& \text{(ii)}& \text{Progressive degeneration of skeletal muscle}\\ \text{(C)}& \text{Muscular dystrophy}& \text{(iii)}& \text{Inflammation of joints}\\ \text{(D)}& \text{Arthritis}& \text{(iv)}& \text{Rapid spasms in muscle}\\ \text{(E)}& \text{Myasthenia Gravis}& \text{(v)}& \text{Bone mass decreased}\end{array}$

The correct option is B A → (iv), B → (v), C → (ii), D → (iii), E → (i)
Following are the diseases mention in the question-
Tetany : Rapid spasms (wild contractions) in muscle due to low $Ca++$ in body fluid.
Muscular dystrophy : Progressive degeneration of skeletal muscle mostly due to genetic disorder.
Osteoporosis : Age-related disorder characterised by decreased bone mass and increased chances of fractures. Decreased levels of estrogen is a common cause of osteoporosis.
Myasthenia gravis : Auto immune disorder affecting neuromuscular junction leading to fatigue, weakening and paralysis of skeletal muscle.
Arthritis : Inflammation of joints.

So, the correct answer is option-c.