The correct answer is: D. Utility based agent
A utility-based agent is an agent that makes decisions based on the expected utility of each possible action. Utility is a measure of how good or bad an outcome is, and the expected utility of an action is the average of the utilities of all possible outcomes of that action.
A utility-based agent can deal with happy and unhappy states by assigning different utilities to each state. For example, an agent might assign a utility of 10 to
a state where it is happy, and a utility of 0 to a state where it is unhappy. The agent would then choose the action that has the highest expected utility.A simple reflex agent is an agent that does not have any internal state. It simply reacts to its environment based on the current state. A model-based agent is an agent that has a model of its environment. This model allows the agent to predict how the environment will change in response to its actions. A learning agent is an agent that can learn from experience. This means that it can improve its performance over time by trial and error.
I hope this explanation is helpful. Let me know if you have any other questions.