What is the colorful nickname of Chefchaouen, Morocco?

Here is the question :

WHAT IS THE COLORFUL NICKNAME OF CHEFCHAOUEN, MOROCCO?

Here is the option for the question :

Blue Pearl
City of a Thousand Blues
Indigo Jewel
Cyan Village

The Answer:

And, the answer for the the question is :

Blue Pearl

Explanation:

[STC0019360]. Chefchaouen drew a high number of Jews fleeing the Spanish Inquisition shortly after its founding in 1471. The immigrants are said to have brought the custom of painting their homes blue to reflect the sky and bring them closer to God. The custom has survived, and today travelers come to Chefchaouen, also known as the ‘Blue Pearl.’