HELP:Point: Espionage in the American Civil War relied more on people’s skills than on gadgetry and inventions. Which sentence best illustrates this point?

Some spies were executed for their involvement in gathering intelligence for the South.
Spies gathered intelligence from letters, newspapers, and interviews with prisoners and deserters.
Use of photography and the telegraph slowly transformed spying into a scientific vocation.
Spying during the Civil War evolved significantly from the amateur efforts of the Revolutionary War.

Read the sentences. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level. lower points may exist. which choice correctly uses the subordinating conjunction “although” to combine the sentences? the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level, although lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level. although lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level although, lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level; although lower points may exist.