Analyzing the Context:
The sentence presents a contrast. Traveling to the spa's remote location could be "hectic" (stressful). However, visitors "made up for the stress by unwinding" in the spa's environment. This implies the spa's environment was the opposite of hectic and stress-inducing; it was calm, peaceful, and relaxing.
- A. effusive: Expressing feelings of gratitude, pleasure, or approval in an unrestrained or heartfelt manner. This describes a manner of expression, not a calming environment.
- B. pacific: Peaceful in character or intent; calm. This fits perfectly with "unwinding" and counteracting "stress" and "hectic" conditions.
- C. duplicitous: Deceitful. This describes a character trait, not an environment.
- D. censorious: Severely critical of others. This describes a critical attitude, not a relaxing environment.
- E. placid: Not easily upset or excited; calm and peaceful, with a smooth undisturbed surface. This also fits perfectly with "unwinding" and counteracting "stress" and "hectic" conditions, as it means calm and tranquil.
- F. blithe: Showing a casual and cheerful indifference considered to be callous or improper. While "cheerful" has a positive connotation, "indifference" doesn't describe a calming environment, and the negative connotation (callous/improper) doesn't fit at all.

Both pacific and placid mean peaceful, calm, and tranquil, which are qualities directly opposite to "hectic" and conducive to "unwinding."