The correct option is option (c), i.e, both (a) and (b) are correct. Sierra Nevada mountain is created by seismic fault and Lewis overthrust in glacier national park in Montana is created by folding.
The Sierra Nevada Fault, an active seismic fault in California's Sierra Nevada mountain massif, runs along its eastern boundary. It extends around 600 km (370 mi) from just north of the Garlock Fault to the Cascade Range, forming the eastern escarpment of the Sierra Nevada.
The Lewis Overthrust is a Rocky Mountain thrust fault structure that can be found in the bordering national parks of Waterton Lakes in Alberta, Canada, and Glacier in Montana, the United States. The structure was created when two tectonic plates collided about 170 million years ago, pushing a wedge of rock up to several miles thick 50 miles (80 kilometres) eastward, where it now lies on top of the softer rock from the Cretaceous period, which is 400–500 million years younger.
To learn more about Sierra Nevada, tap here:
brainly.com/question/3985743
#SPJ4
