Answer:
The sentence "John is rich but humble" could be classified as convectional implicature because it implies a relationship between being rich and being arrogant. The implicature arises because it is commonly assumed that wealthy people are often arrogant or boastful about their wealth. Therefore, the use of the word "but" suggests that it is unusual or unexpected for someone who is rich to also be humble. This creates an implicature that the speaker intends to communicate, even though it is not explicitly stated in the sentence.
Step-by-step explanation: