Final answer:
When a physician accepts payment for patient referrals, it's called a kickback, which is an unethical and illegal practice because it compromises patient care for financial gain.
Step-by-step explanation:
If a physician accepts payment from another physician solely for the referral of a patient, both are guilty of an unethical practice called kickback.
This practice is considered unethical because it can influence the physician's decision-making process, prioritizing financial gain over the patient's best interest and care.
The acceptance of kickbacks is prohibited under various healthcare laws and regulations to ensure that medical care decisions are made based solely on the health needs of patients, not on financial incentives.