According to researchers, the stress experienced by an individual while being introduced to a new culture indicates that the individual .

indicates that the individual is experiencing a culture shock

Explanation:

A culture shock occurs when a person experiences great stress, confusion, anxiety, and other negative emotions, after being introduced to a culture that is different from his native one.

This is a common occurance in individuals that travel a lot, either for reasons of leisure or work.

the answer should be

the simple past tense of strive.

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