Which of the following would constitute a real estate license law violation?

Combining an option with a listing agreement without obtaining informed seller consent would constitute a real estate license law violation. This is because it goes against the principles of honesty and transparency in real estate transactions. While promoting a property on social media, using a personal phone for business calls, and sending emails to potential clients are common practices in the real estate industry, they do not violate any license laws as long as they are carried out ethically and with adherence to relevant laws and regulations. Therefore, options A, C, and D are incorrect choices.