Why are hard wallets considered secure for storing cryptocurrencies?

Hard wallets, often referred to as hardware wallets, are considered secure for storing cryptocurrencies primarily because they store private keys offline. This means that the keys, which provide access to the cryptocurrency, are not exposed to the internet. By being disconnected from online networks, hard wallets protect against hacking attempts, malware, and various types of cyber threats that target online or software wallets.

Additionally, since the private keys are generated and stored in the hardware itself, they remain safe even when the device is connected to a computer or another device for transactions. This offline storage is crucial, as the vast majority of security breaches in the cryptocurrency space occur due to online storage or access methods.

The other options do not contribute to the security of hard wallets. Being connected to the internet exposes wallets to potential attacks. Monitoring through online accounts presents the risk of account breaches, compromising the security of the stored cryptocurrency. Integrated smart contracts are not a feature of hard wallets; they are more associated with blockchain platforms where contracts can execute automatically based on predetermined conditions. Thus, the strength of hard wallets lies in their offline key storage, providing a robust layer of security for cryptocurrency holdings.