Which of the following actions is an example of tortious interference?

Tortious interference refers to situations where one party intentionally disrupts or interferes with the contractual or business relationships of another party, resulting in harm or economic loss. The action of convincing a party to breach a contract clearly aligns with this definition. In this scenario, one party directly persuades another to act contrary to their existing contractual obligations, which not only undermines the relationship between the parties involved but can also lead to significant legal and financial repercussions.

The other actions listed do not fit the specific framework of tortious interference. Filing a lawsuit, while it can create friction, is generally a legal right and does not constitute interference in the sense of harming a contractual relationship. Similarly, significantly underbidding a competitor may be considered aggressive business practice or competition but does not involve persuading a third party to breach a contract. Providing poor service intentionally may reflect unethical practices but does not typically involve direct interference with a contractual relationship, unless it specifically causes a breach. Thus, the decisive aspect that makes the choice of convincing a party to breach a contract an instance of tortious interference is its intentionality and the direct impact it has on existing contractual obligations.