Final answer:
The terms "fname" and "lname" are examples of JSON keys, which are the strings that define the properties of an object in a JSON structure.
Step-by-step explanation:
The examples given, "fname" and "lname", represent JSON keys. In JSON, which stands for JavaScript Object Notation, keys are used to define the properties of an object and they are always strings. These keys are paired with values that can be strings, numbers, arrays, objects, or boolean values. In the context of the question, "fname" and "lname" would typically be associated with values representing a first and last name. For instance, the JSON structure might look like this:
{
"fname": "John",
"lname": "Doe"
}
Therefore, the correct answer is b) JSON keys.