AP English Language

Passage:

"Rushing through the crowded marketplace, the skilled merchant, known for his sharp bargaining skills, quickly scanned the stalls, his experienced eyes searching for rare and valuable artifacts. The bustling environment, filled with the scent of exotic spices and the sound of eager negotiations, made each transaction an intricate dance of strategy and persuasion. Carefully observing each vendor’s reactions, he selectively chose items that were not only authentic but also undervalued, ensuring a profitable return on his investment."

Which of the following words or phrases function as adverbial modifiers in the passage?