Answer:
Natural language understanding (NLU) is a branch of natural language processing, which involves transforming human language into a machine-readable format.
Explanation:
NLU is branch of natural language processing (NLP), which helps computers understand and interpret human language by breaking down the elemental pieces of speech. While speech recognition captures spoken language in real-time, transcribes it, and returns text, NLU goes beyond recognition to determine a user's intent.
problem/cause/solution
The passage first identifies the problem as the tires "piling up in empty lots." Then it is explained how those tires got there: the cause. The author says that since "it is expensive and dangerous to dispose of tires" people don't dispose of them and they just keep piling up. Then the passage ends with a solution. The author mentions how tires can be shredded and turned into rubberized asphalt for paving projects.
B. Eager to eat, Caleb immediately joined the buffet line.