Block size =$16B$
Total No of Block=$64$
Memory block Number=$\frac{\text{Byte}\ \text{address}}{\text{Block}\ \text{Size}}$
=$\frac{1206}{16}$
=75
Now we have to find a cache block number related to memory block number.
So In Direct Mapped cache,
$\text{Cache block Number}=\text{Memory block Number $\color{magenta}{\text{mod}\;}$(Total Number of a block in cache)}$
=$75\;\text{mod}\;64$
=$11$
So option C is correct.