What is the difference between System $1$ and System $2$ thinking, and which is best for ethical decision$-$making?

a$.$

System $1$ thinking is fast, intuitive, and emotional. System $2$ thinking is slower, more deliberate and more logical processing. Due to the complexity of most ethical dilemmas, System $2$ thinking is more useful to come up with an optimal decision.

b$.$

System $1$ thinking is slow, deliberate and logical$.$ System $2$ thinking is fast, reactive and spontaneous. Due to the importance of determining a quick solution to most ethical dilemmas, System $2$ thinking is more useful.

c$.$

System $1$ thinking is fast, intuitive, and emotional. System $2$ thinking is slower, more deliberate and more logical processing. Due to the need for a quick resolution to most ethical dilemmas, System $2$ thinking is more useful to come up with an optimal decision.

d$.$

None of the above