Final answer:
The advanced instruments used to detect small changes in wind velocity and air pressure provide the benefit of issuing early tornado warnings. So the correct option is A.
Step-by-step explanation:
The instruments used to detect small changes in wind velocity and air pressure are valuable tools for identifying and tracking tornadoes. These instruments can provide the benefit of issuing early tornado warnings by detecting signs of tornado formation. By analyzing the data from the instruments, meteorologists can identify the conditions that are conducive to tornado development and provide warnings to affected areas. However, it's important to note that these instruments cannot predict tornadoes weeks in advance or prevent tornado formation.