Concept:
To find the number of memory chips required, divide the required memory size by the size of one chip.
Step 1: Required memory.
\[
4096\times16
\]
Step 2: Size of one memory chip.
\[
256\times16
\]
Step 3: Compare word size.
Both required memory and chip memory have word size:
\[
16
\]
So, only the number of words needs to be expanded.
Step 4: Find number of chips.
\[
\text{Number of chips}=\frac{4096}{256}
\]
\[
=16
\]
\[
\therefore \text{Correct Answer is (A)}
\]