Which is the correct way to join these two sentences with a coordinating conjunction?

Tom walks slowly. He always arrives on time.

b.Tom walks slowly, but he always arrives on time.

c.Tom walks slowly. But he always arrives on time.

d.Tom walks slowly but he always arrives on time.

e.Tom walks slowly: but he always arrives on time.

f.Tom walks slowly but, he always arrives on time.



plz answer question carefully