Step 1: Examine Statement A.
Ionization potential (or ionization energy) is the minimum energy required to remove the most loosely bound electron from an isolated gaseous atom.
As we move down a group in the periodic table:
Atomic radius increases
and
Shielding effect increases
Due to the increased distance of the valence electron from the nucleus and greater shielding by inner electrons, the attraction between the nucleus and the outermost electron decreases.
Therefore, less energy is required to remove the electron.
Hence, ionization potential generally decreases down a group.
Thus, Statement A is correct.
Step 2: Examine Statement B.
Sodium \((Na)\) and Potassium \((K)\) belong to Group 1 of the periodic table.
Their electronic configurations are
\[
Na : 1s^2\,2s^2\,2p^6\,3s^1
\]
\[
K : 1s^2\,2s^2\,2p^6\,3s^2\,3p^6\,4s^1
\]
Potassium has one additional shell compared to sodium.
Therefore,
\[
\text{Atomic radius of K} \gt \text{Atomic radius of Na}
\]
and the outermost electron in potassium experiences a weaker nuclear attraction.
Hence,
\[
IE_1(K) \lt IE_1(Na)
\]
Therefore,
\[
IE_1(Na) \gt IE_1(K)
\]
Thus, Statement B is also correct.
Step 3: Final conclusion.
Both Statement A and Statement B are correct.
Therefore,
\[
\boxed{\text{Both A and B are correct}}
\]
Hence, the correct option is
\[
\boxed{(2)}
\]