Step 1: Identify the direct speech.
The direct speech in this case is: "March forward and kill the enemy."
Step 2: Conversion to indirect speech.
In indirect speech, we need to change the reporting verb to a suitable form (in this case, "told") and remove the quotation marks. We also change the pronoun ("his soldiers") to reflect the subject in the sentence.
Step 3: Final Conversion.
Thus, the correct indirect narration is: "The General told his soldiers to march forward and kill the enemy."
Final Answer:
\[
\boxed{\text{The General told his soldiers to march forward and kill the enemy.}}
\]