Zakreśl poprawne zakończenie zdania: W drugiej połowie XX w. liczba turystów zagranicznych na świecie wzrosła

Unclear question. However, here's the clearer rendering;

Circle the correct ending of the sentence: In the second half of the 20th century, the number of foreign tourists in the world increased.

Explanation:

The sentence appears to be correctly written. However, it could be modified with an adverb such 'greatly'. Which could be written as; In the second half of the 20th century, the number of foreign tourists in the world increased.