Which of the following words is closest in meaning to “Endeavour”?

Endeavour means effort.

• Correct answer - effort: it has the same meaning as Endeavour.
• intrude: to enter uninvited - wrong, it does not mean the same as Endeavour.
• strengthen: to make stronger - wrong, it does not mean the same as Endeavour.
• captivate: to charm - wrong, it does not mean the same as Endeavour.