Which is the best tour to take is the best tour at Mammoth Cave?

We are visiting Mammoth Caves late August. Our group has 2 adults and 2 teenagers (17 and 19 years old). We have about half a day and want to get an overview of the most famous parts of Mammoth Cave. We want variety and amazing views of the cave. What tour do you recommend and why did you like this tour in particular?