By the 1700s, maize was a major crop in parts of Africa and Europe. Which transfer explains how it got there?

Potatoes became staple foods in Ireland, Russia and other parts of Europe after the 1500s. What was the direction of this transfer?

Tomatoes are central to many Mediterranean cuisines today. Which movement brought them to Europe?

Cassava became a major food crop in parts of West and Central Africa after Portuguese Atlantic trade expanded. Which transfer best explains its spread?

Chocolate drinks became popular in Spain and then across Europe in the 1500s and 1600s. Which source region first supplied cacao to Europeans?

Horses transformed transportation and hunting for many Plains peoples after the 1500s. Which Columbian Exchange movement brought them there?

Sugarcane plantations expanded in the Caribbean and Brazil after European colonization. Which direction of transfer fits sugarcane?

Smallpox epidemics devastated many Indigenous American communities soon after 1492. Which exchange direction explains the disease pattern?

Spanish is official from Mexico to Peru even where many Indigenous languages remain. What best accounts for that broad cultural landscape?

French is widely used in Senegal, Côte d'Ivoire and Haiti, places separated by oceans and older local languages. Which process best explains the pattern?

English has official or major administrative roles in India, Nigeria and Jamaica. What historical engine most directly explains that shared trait?

Portuguese is dominant in Brazil and official in Angola and Mozambique, territories on different continents. Which explanation fits best?

Catholicism is deeply rooted in the Philippines and much of Latin America. Which force best explains that shared religious pattern?

Nearby Caribbean islands often differ in official language and church tradition, such as French and Catholic Martinique and English and Anglican Barbados. What created that pattern?

Dutch is official in Suriname, and Dutch legal and school influences remain historically important in Indonesia. Which process best explains this link?

French administrative terms and Catholic institutions are widespread in the Democratic Republic of the Congo, far from Europe. What historical cause fits best?

Islam reached Timbuktu and other Sahelian cities of West Africa through merchants and scholars from North Africa. Which route carried it?

Arabic loanwords and Islam became important on the Swahili Coast through merchants traveling between East Africa and Arabia. Which route fits?

Buddhism moved from India into Central Asian oasis towns and then into China. What route carried this diffusion?

Hindu-Buddhist ideas and Sanskrit terms reached royal courts in Java, Sumatra and mainland Southeast Asia from India. Which route carried them?

Papermaking knowledge moved from China to Samarkand, then to Baghdad and later Europe. Which route best matches this path?

Muslim trading communities and mosques appeared in port cities from Gujarat in India to Malacca in Malaysia. Which route spread Islam there?

Arabic numerals and mathematical texts reached medieval Europe through Muslim-ruled Spain and Sicily. Which network helped carry them?

On Brazil's Bahia coast, Candomblé, drumming and foodways show strong West African roots. What explains how these traits reached Brazil?

Gullah Geechee communities on the Sea Islands preserve language features, stories and foodways with West African connections. What historical engine fits?

Haitian Vodou blends West African religious traditions with Catholic symbols. What process produced it?

Santería in Cuba connects Yoruba deities with Catholic saints. Which historical movement best explains why Yoruba-linked practices are in Cuba?

Blues and spirituals in the U.S. South show African musical influences in call-and-response, rhythm and performance. Which cause best explains that pattern?

Carolina Lowcountry rice farming drew on knowledge from West African rice-growing regions. What explains that cultural transfer?

Capoeira is a Brazilian art that combines music, movement and combat. Which historical cause best explains its roots?