Number of sets in cache $= v$.
The question gives a sequencing for the cache lines. For set $0$, the cache lines are numbered $0, 1, .., k-1$. Now for set $1$, the cache lines are numbered $k, k+1,... k+k-1$ and so on.
So, main memory block $j$ will be mapped to set $(j \ \text{mod} \ v)$, which will be any one of the cache lines from $(j \ \text{mod } v) * k \ \text{ to } (j \ \text{mod } v) * k + (k-1)$.
(Associativity plays no role in mapping- $k$-way associativity means there are $k$ spaces for a block and hence reduces the chances of replacement.)
Correct Answer: $A$