Let's break down the sentence and fill in each blank based on the context:

Analyzing the Context:
The sentence describes a situation where someone's behavior ("His (i) $\qquad$ ") "stunned everyone in the room." This "stunning" effect is particularly notable "because the hostess had (ii)
$\qquad$ his virtues to all of the guests before his arrival." This implies a contrast: the hostess spoke highly of him, but his actual behavior was surprisingly negative or inappropriate, causing shock.

Blank (i): We need a word for a behavior that would stun people, especially when the person had been praised beforehand. This suggests a bold, shameless, or impudent act.
- A. perspicacity: The quality of having a ready insight into things; shrewdness. This is a positive intellectual quality and would not stun people in a negative way, especially after being praised.
- B. obsequiousness: Excessive obedience or attentiveness; servile deference. While it can be annoying, it's unlikely to "stun" everyone, especially if the person's virtues were previously lauded.
- C. effrontery: Shameless or impudent boldness; audacity. This fits perfectly. If someone has been praised for their virtues, and then they display outrageous or disrespectful boldness, it would certainly stun people.

Therefore, for Blank (i), effrontery is the best fit.


Analyzing Blank (ii): The hostess had done something to "his virtues" before his arrival, which makes his later stunning behavior even more surprising. This means she must have highlighted or praised his virtues.
- D. extolled: Praised enthusiastically. This fits the context of highlighting virtues and creating a contrast with later shocking behavior.
- E. refuted: Proved (a statement or theory) to be wrong or false; denied. This is the opposite of praising virtues.
- F. regaled: Entertained or amused (someone) with talk. While she might have entertained guests, the phrase "regaled his virtues" isn't a natural collocation, and "extolled" much more directly means to praise or highlight virtues.

Therefore, for Blank (ii), extolled is the best fit.

The completed sentence:
"His effrontery stunned everyone in the room, especially because the hostess had extolled his virtues to all of the guests before his arrival."