How does the CI server know a step failed?

QuizEasyAsked in: Capgemini, Google, Salesforce, TCS, Zupee

Tests fail during a CI step. How does the CI server know the step failed?

Choose one answer.

The test command exits with a non-zero exit code
It reads the HTML report
It searches the log for the word "error"
It cannot know; someone must check by hand

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