Verizon hires people from all over the world with different nationalities. This represents which level of diversity?

This represents a Surface-level of diversity.

Also called demographic diversity, social category diversity, bio-demographic diversity, and observable individual differences. Surface level diversity are those differences that are easily noticeable such as age, gender, ethnicity/race, culture, language, disability etc. Surface level diversity is easy to be measured and managers/recruiters can fall into the wrong practice of discrimination based on these factors. For example, thinking that performance degrades with age, they might prefer younger workforce.