Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: The following statements are from an article in a fitness magazine. Which of these is an opinion?
People should exercise because it makes them feel better.
I believe that running is the best cardio exercise for weight loss.