Question

In the Battle of Roncevaux Pass in 778, the rearguard of the Frankish army, under the command of Roland, was obliterated due to an ambush by the Basque army, an event made famous in La Chanson de Roland.

• A. In the Battle of Roncevaux Pass in 778, the rearguard of the Frankish army, under the command of Roland, was obliterated due to an ambush by the Basque army, an event made famous in La Chanson de Roland
• B. In the Battle of Roncevaux Pass in 778, the Basque army ambushed the Frankish army, the rearguard of the Frankish army, under the command of Roland, was obliterated, and the event was made famous in La Chanson de Roland
• C. La Chanson de Roland made famous the obliteration, due to an ambush by the Basque army, of the rearguard of the Frankish army, under the command of Roland, at the Battle of Roncevaux Pass in 778
• D. In La Chanson de Roland, the Basque army ambushed the rearguard of the Frankish army, under the command of Roland, and obliterated them, and this event was famous at the Battle of Roncevaux Pass in 778
• E. In the Battle of Roncevaux Pass in 778, the rearguard of the Frankish army, under the command of Roland, ambushed and obliterated by the Basque army, an event made famous in La Chanson de Roland

Answer 1

The correct option is C La Chanson de Roland made famous the obliteration, due to an ambush by the Basque army, of the rearguard of the Frankish army, under the command of Roland, at the Battle of Roncevaux Pass in 778

La Chanson de Roland made famous the obliteration, due to an ambush by the Basque army, of the rearguard of the Frankish army, under the command of Roland, at the Battle of Roncevaux Pass in 778.
The "due to" phrase in this sentence correctly modifies the noun "obliteration." We could drop the "due to" phrase, and the remaining sentence would still make sense.

The word "due" is an adjective, and it is grammatically incorrect for any adjective to modify a verb. Using "due to" to modify verbs, actions, is an extremely common mistake in English.