Option D: They vary based on popularity and market demand of products designed with the language.
is the correct answer that best categorizes the state o programming languages over time.
With the advent of time, new programming languages are also introduced. But this doesn't means that the older ones are loosing or gaining popularity because of others. Changing or development of product design in the market tells us that the programming languages have their own specific properties on the basis of which they are used.
From this we can conclude that a programming language gets popular due to its specifications and features that may not get diminished by the features o other programming languages.