Question

endeavor has the same or almost the same meaning as: strive assure prepare decline

Explanation:

"Endeavor" means to try hard to do something. "Strive" also means to make great efforts to achieve something. "Assure" means to make someone feel certain. "Prepare" means to get ready. "Decline" means to refuse or go down. So "endeavor" and "strive" have similar meanings.

Answer:

strive