What part of speech is represented by the word in parentheses: It took a great deal of (courage) to dive into the swimming pool.

The word in parentheses, "courage," is classified as an abstract noun because it represents a concept or quality rather than a physical object that can be perceived through the senses. An abstract noun refers to ideas, emotions, and states of being. In this case, "courage" signifies bravery and the quality of being able to confront fears or challenges, which are intangible characteristics.

While the other options include parts of speech that could be confused with this noun—such as adjectives, which describe qualities, and verbs, which denote actions—a correct understanding of "courage" points to its status as an abstract noun, capturing the essence of bravery itself. Additionally, though nouns can be countable or uncountable, "courage" does not fit the criteria of a countable noun, as it does not have a plural form or refer to entities that can be counted.