Step 1:
Gaṇas are combinations of Laghu and Guru syllables.
Step 2:
Bhagaņa corresponds to SII, while Jagana corresponds to ISI.
\[
A \rightarrow II,\quad B \rightarrow I
\]
Step 3:
Sagaņa corresponds to IIS and Nagana corresponds to III.
\[
C \rightarrow IV,\quad D \rightarrow III
\]
Step 4:
Thus, the correct sequence is:
\[
A-II,\; B-I,\; C-IV,\; D-III
\]
Hence, the correct answer is:
\[
\boxed{\text{(4)}}
\]