The correct answer is D. no article.
The word "meat" is a non-count noun, which means it does not have a plural form and is not preceded by an article. Other examples of non-count nouns include water, air, milk, and rice.
In the sentence "He eats a lot of meat," the word "meat" is not referring to a specific type of meat, such as beef or chicken. It is simply referring to meat in general. Therefore, no article is needed.
If the sentence were referring to a specific type of meat, then an article would be needed. For example, "He eats a lot of beef." In this sentence, the word "beef" is a count noun, which means it has a plural form and is preceded by an article.
I hope this explanation is helpful! Let me know if you have any other questions.
