In 1513, balboa and his crew reached a(n) that connected north america and south america.
a-circumnavigation
b-isthmus
c-monopoly
d-colony
e-missionary
f-persecution

  B- Isthmus.

Explanation:

  An isthmus is also known as a land bridge and is a narrow piece of land that connects two larger areas across an expanse of water.

  Vasco Nuñez de Balboa during his sailing through the Caribbean Coast heard from the natives about a South Sea. In 1513 the Isthmus of Panama to the Pacific Ocean and became the first European to seen and reach the Pacific from the New World.

  Usually, canals are built across isthmuses.

  I hope this answer helps you.

must repent and believe in god.

or the book

journey across time - chapter 10 "the rise of christianity"