Final answer:
Subliminal is best matched with unperceived, phlegm with mucus, persona with public personality, frivolity with silliness, and promontory with a high point of land.
Step-by-step explanation:
For the word in parentheses (subliminal), the best match is B) unperceived. Subliminal messages refer to messages that are not consciously perceived but may still affect an individual's mind or behavior.
Rudy's mother warned him not to eat ice cream when he was sick as it would add to his (phlegm), which is best matched with B) mucus. Phlegm is a specific kind of mucus produced by the respiratory system, particularly when an individual is ill.
The counselor explained that everyone has a (persona) that they use in uncomfortable situations, which matches best with B) public personality. A persona is an aspect of someone's character that is presented to or perceived by others, especially in contrast to the person's true self.
The flashy new outfit as a display of (frivolity) is best matched with C) silliness. Frivolity refers to a lack of seriousness or sense, often characterized by unnecessary or gaudy displays.
Just west of the river is a (promontory) where a fort has stood for hundreds of years, which is described as C) high point of land. A promontory is an elevated piece of land that juts out into a large body of water.