Answer:
Alonso Quixano's obsession with chivalric romance stories turns into insanity when he gives up his idle days and takes on the persona of a knight-errant named Don Quixote. Armed with shabby armor and a homemade helmet, he and his elderly horse, Rocinante, set off for adventure in the Spanish countryside. He dedicates his career as a knight to a local woman he refers to as Dulcinea del Toboso, despite the fact that he has never spoken to her.
Explanation:
He was frustrated for obvious reasons. But was described as 'perplexed and still' because he expected a answer from the inmates that were inside the house, but instead of answering his repetitive calls, they chose to give no response leaving the traveler to experience his 'stillness'.
The answer is D) doubt. I know this because when you use context clues this the most understandable.
Placid means peaceful and tranquil.
The best synonym for placid would be C. peaceful.
