Which of the following is true for smart contracts?

Smart contracts are self-executing contracts with the terms of the agreement directly written into code. They facilitate, verify, and enforce the negotiation or performance of a contract without the need for intermediaries.

The first statement holds true as smart contracts outline the specific terms and conditions associated with transactions. They automatically execute actions when predefined conditions are met, eliminating the ambiguity often present in traditional contracts.

The second statement is also accurate; smart contracts can interface with external applications through various mechanisms, such as oracles, which allow them to access real-world data and trigger actions based on that information. This expands their usability beyond just the blockchain environment.

The third statement reinforces the applicability of smart contracts in peer-to-peer transactions. They allow individuals to transact directly with each other, reducing the need for traditional intermediaries like brokers or banks, which can lower costs and increase transaction speed.

Thus, all these characteristics—outlining transactions, interfacing with external applications, and enabling peer-to-peer transactions—culminate in the comprehensive understanding that "All of the above" is indeed true for smart contracts.