Final answer:
Option D, 'It's time for us to heed the lessons we've learned, look to the future, and live in the now,' is the most precise language choice as it is concise and clearly communicates the intended imperatives without unnecessary repetition.
Step-by-step explanation:
The question involves selecting the option that uses the most precise language for a particular phrase in a sentence. Option D uses the most precise language: "It's time for us to heed the lessons we've learned, look to the future, and live in the now." This option is concise and clearly separates the actions into three distinct imperatives without unnecessary repetition, which are to heed past lessons, look forward to the future, and live in the present. It effectively conveys the intended meaning without any ambiguity which could result from the underlined parts in the other options.