d. reasonable and logical
Bear in mind, what a Stoic would have meant by "reasonable and logical" may be a little more refined than how you think of those terms. Also, even the concept of "happiness" would have a different feel in Stoic thought than in modern thought. The Stoics believed there was an underlying logic guiding the universe. Their term for this was "logos," the Greek word for "word" or "reason" or, I suppose we could also translate it as "logic" (since that's where we get our English word "logic.") The sternest of the Stoics believed there was really nothing we could do to alter this guiding force of all things, that we needed to put aside our passions and align our minds with the way the world functions. Other Stoics, especially those involved in politics like Marcus Aurelius (a Roman emperor), saw it as our duty to try to keep not only ourselves but society aligned with this "logos" or reasonableness of the universe.