Software complexity: Software engineering has developed some popular measurements of software complexity.
The McCabe essential complexity metric is perhaps the most often used. This is also known as cyclomatic complexity. It is a metric for the number and depth of routines in a piece of code. Software complexity is a way to describe a specific set of characteristics of your code. These characteristics all focus on how your code interacts with other pieces of code. Different measurements of software complexity are,
The Halstead Metrics.
The Cyclomatic Complexity.
Counting Lines of Code. Code Shape.
Coupling and Cohesion.
Hence the correct answer is the Number of lines of code (LOC)