Which accurately describes how Portuguese exploration efforts affected native African civilizations?

The Portuguese spread syphilis to African civilizations, killing nearly 20% of the population.

The Portuguese explorers traded fox furs, corn, and coffee with African coastal tribes.

The Portuguese spread Judaism to African tribes, teaching ancient Hebrew practices.

The Portuguese traded or kidnapped Africans, eventually starting the transatlantic slave trade.

what are the others?

map scale refers to the relationship (or ratio) between distance on a map and the corresponding distance on the ground. for example, on a 1: 100000 scale map, 1cm on the map equals 1km on the ground.

the option which was not a function of missionaries in the northwest was the first one - they established posts for trading furs and other goods.

missionaries were sent around the world to spread religion and their knowledge and others - they were not merchants who sold furs and other goods.