Final answer:
The correct statement that indicates an understanding of wearing a cardiac event monitor at home is 'I can take showers while wearing the monitor'. The option (1) is correct.
Step-by-step explanation:
Out of the given statements, the one that indicates an understanding of the instruction for wearing a cardiac event monitor at home is I can take showers while wearing the monitor. This statement shows that the patient understands that the monitor is safe to be exposed to water and can be worn during activities such as showering.
The other statements are incorrect: the monitor does not keep track of all daily activities, it is not recommended to use electronic blankets while wearing the monitor, and the patient should not replace the batteries themselves if they fail. Therefore, option (1) is correct.