What is the term for making unsolicited, inappropriate phone calls?

The term "obscene telephone calls" specifically refers to the act of making unsolicited and inappropriate phone calls, typically involving explicit, offensive, or harassing content. This behavior is recognized as a form of harassment and is often subject to legal penalties. These calls can infringe upon the privacy and comfort of the recipient, which is why they are categorized under laws against harassment and telecommunications violations.

In the context of this question, the other choices do not relate to the act of making inappropriate phone calls. For example, "stolen vehicle" pertains to a crime involving the theft of a car, while "reckless behavior" encompasses a broader range of unsafe practices that do not specifically address phone communications. "Parking violation" relates to improper parking practices regarding vehicles. Therefore, "obscene telephone calls" is the most accurate answer as it directly addresses the nature of the behavior described in the question.