Look at these details from a paragraph about the same topic:

Question

To train for a race, sled dogs run for many hours each day.
Sled dogs practice pulling a heavy sled so they get used to the weight.
Sled dogs also practice running on different kinds of ground.
Choose the main, or central, idea that ties all the details together.

Answer 1

The main idea that ties all the details together is that sled dogs engage in various training activities to prepare for races.