Final answer:
The denotation of the word 'floundered' in the given context is to 'struggle.' Thus, the correct answer is option 2 - struggled, indicating Mariah's difficulty in answering the questions.
Step-by-step explanation:
The question asks for the denotation, or the literal meaning, of the word floundered as used in the provided sentence. The correct denotation for floundered in the context of the sentence "Mariah’s voice shook and her hands fluttered as she floundered helplessly to answer the difficult questions Steven was asking her." is to struggle with difficulty or ineffectiveness. Therefore, the correct answer is option 2 - struggled. This signifies Mariah's difficulty in answering the questions, implying that she is not answering them with ease but is instead having trouble responding.