A is incorrect: Increasing the temperature influences response creativity and randomness but does not directly address an agent's over-reliance on explicit context for simple conversational elements.

B is incorrect: Using a smaller model might reduce capabilities and understanding, but it wouldn't specifically fix an 'over-grounded' issue related to conversational handling.

C is correct: To address this, the system's governing instructions need refinement, clearly differentiating between factual accuracy requirements ('grounding') and expectations for informal dialogue or 'general chat'.

D is incorrect: Deleting the context would remove factual grounding, which is not the goal. The aim is to balance factual responses with general conversation.