What will be logged when executing the following code: emp.fullName ='John Smith'; console.log(emp.fName);?

The code snippet provided aims to log a property of the emp object. In this case, emp.fullName is being set to the string 'John Smith', but the code attempts to log emp.fName.

For emp.fName to return 'John', the emp object must have a property fName defined and initialized with the value 'John'. Given that emp.fullName is being set but emp.fName is not defined elsewhere in the code, logging emp.fName will result in undefined.

The correct interpretation is that without additional context revealing a definition for fName, the output will indicate that fName is nonexistent or empty, leading to the return of undefined. Therefore, under typical JavaScript behavior, the logged result of console.log(emp.fName) when fName hasn't been assigned a value will yield undefined.

This understanding emphasizes the importance of ensuring that properties are declared and initialized before they are accessed to avoid unexpected results such as undefined.