In John Steinbeck's "The Turtle," what does the turtle do as it rests after climbing the side of the road?

It hurries away from the cars.

It retreats into its shell.

It rolls down the side of the embankment.

It eats some wild oats.

The writer says that the turtle at the roadside land crawled, turning aside for nothing, dragging his high-domed shell over the grass: His hard legs and yellow-nailed feet threshed slowly through the grass, not really walking, but boosting and dragging his shell along. This may be denoting a rolling down the side of the embankment