Santiago is the name ofsantiago is the name of

a.

chile’s capital.

b.

a chilean saint.

c.

a national park

a. 

Chile’s state capital.

Your answer should be Chile's capital.

Betray, destroy, and obey do not need to be changed to add the suffix -ed, because the "y" at the end of each word is preceded by a vowel  (so  they would be spelled  "betrayed," "destroyed," and "obeyed").

but hurry is different; it has to  be spelled "hurried" because the "y" at the end of "hurry" is preceded by a consonant.