Which of the following European countries started geographical exploration which resulted in the colonization of America, Asia and Africa?

Correct option is A

Portugal and Spain were pioneering states in the Age of Discovery, spearheading European exploration of new territories in the 15th and 16th centuries. Portugal, under Prince Henry the Navigator, initiated the discovery of the Atlantic archipelagos and the African coast, culminating in Vasco da Gama's voyage to India. Spain, following the union of its crowns, financed Christopher Columbus's expedition leading to the discovery of the Americas. These explorations opened the routes for extensive maritime empires in Asia, Africa, and the Americas, setting the stage for several centuries of European colonization and exploitation of these continents.
Information Booster:
 France and England began their significant explorations slightly later, focusing on North America and parts of Asia. Their colonial empires expanded extensively during the 17th and 18th centuries.
 Germany and Italy were not unified countries during the early period of exploration and did not play a leading role in the early stages of the European overseas expansion. Their participation in colonization came much later, with Italy and Germany engaging in colonial pursuits in the late 19th and early 20th centuries.