Final answer:
Words such as speculative, unscrupulously, new Eldorado, and innuendos add depth and nuance to the text, contributing to the development of the central idea.
Step-by-step explanation:
Words such as speculative, unscrupulously, new Eldorado, and innuendos contribute to the development of the central idea by adding depth and nuance to the text. These words create a tone of uncertainty and suspicion, suggesting that the central idea is not straightforward or easily understood. For example, the use of the word 'speculative' implies that the central idea is based on conjecture rather than concrete evidence. Similarly, 'unscrupulously' implies unethical behavior, hinting at the potential negative consequences of the central idea. 'New Eldorado' and 'innuendos' add a sense of mystery and hidden meanings, making the reader curious and engaged in deciphering the central idea.