Question

What strategy should he use to improve his communication with employees from other cultures?

Answer 1

I think that the best option is: 

B.Interact more with people from different backgrounds.

In general, if we interact more with people of different cultures, we can learn to communicate better. This is actually true for everything: if we do something a lot, we become better at it and we learn it.

What is not good is limiting communication: this will only potentially offend other people.