An Otherwise Healthy 40-Year-Old Man Comes to the Office Due

An otherwise healthy 40-year-old man comes to the office due to an enlarging lipoma.  The patient has had a lipoma on his upper back for the past three years, and it has rapidly increased in size over the past 6 months.  Physical examination shows an 8-mm raised lesion with well-defined borders on the upper back.  Excisional biopsy of the lesion is planned.  Local anesthesia is administered via an infiltrating injection of lidocaine mixed with epinephrine.  Which of the following is the most likely impact of mixing the latter medication with the anesthetic agent?

A) Altered neurotransmitter levels of nociceptive fibers
B) Decreased pain during subcutaneous infiltration
C) Increased anesthesia efficacy by synergistic effect
D) Increased anesthesia potency by decreasing tissue pH
E) Prolonged duration of action of the anesthetic agent