GMAT Sentence Correction (SC) | Geologists believe that the warning signs for a major

Geologists believe that the warning signs for a major earthquake may include sudden fluctuations in local seismic activity, tilting and other deformations of the Earth’s crust,changing the measured stain across a fault zone, and varying the electrical properties of underground rocks.

Issue:Parallelism | Meaning

Analysis:
1. The sentence can be broken down as following and the main issue at play here is parallelism. We need to make sure that all the warnings sign should be parallel is form.
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