Answer: B. Sibley charted paths to points further west.
Step-by-step explanation:
During the Civil War, Major Sibley planned to conduct a New Mexico campaign in which he hoped to capture the cities of Albuquerque and Santa Fe as well as Fort Union.
From Fort Union, Major Sibley hoped to push further west to California and establish naval bases from which they could get supplies and escape the Union blockade of Southern ports.