Choose the grammatically correct sentence from the option given below:

The correct answer is Option (1) → A soldier is trained never to fight in a cowardly manner.

Adjectives ending in -ly:

• Cowardly ends in -ly but is an adjective (like friendly, lovely, lonely); it means lacking courage.
• Such adjectives have no adverb form, so we say in a cowardly manner (or way).
• Never stands just before "to fight": the soldier is trained, and what the training rules out is fighting like a coward.
  Example: It was a cowardly attack on unarmed people.

Why the Other Options are Incorrect?

Option 2: A soldier is trained never to fight in a coward manner. — Incorrect. Coward is a noun (a person who lacks courage); before "manner" the adjective cowardly is needed.
Corrected: A soldier is trained never to fight in a cowardly manner.

Option 3: A soldier is never trained to fight coward like. — Incorrect.

• "Coward like" is not standard English; the correct forms are "like a coward" or "in a cowardly manner".
• "Never trained to fight" says that soldiers get no training to fight at all, which changes the meaning.
• Corrected: A soldier is trained never to fight like a coward.

Option 4: A soldier is trained to fight never as a coward. — Incorrect. Never is in the wrong place; it should come before "to fight" (trained never to fight as a coward).
Corrected: A soldier is trained never to fight as a coward.