Answer: How to solve 'Unresolved reference: arch' from "import android.arch.lifecycle"?

I changed my dependency from

testImplementation "android.arch.core:core-testing:2.2.0"

to

testImplementation "androidx.arch.core:core-testing:2.2.0"

This is because my project recommends imports from androidx artifacts not from android.

My problem was solved 100%