Answer
The correct definition of the underlined word "libations" in the context of the sentence provided is:
**the pouring of drink as an act of respect**
This definition is the best fit because "libations" generally refers to drinks, especially alcoholic ones, often consumed or poured out as part of a ritual or as an offering in honor or respect of someone. The sentence implies that the drinks at the party were enjoyed as a way to honor the hostess.