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

Mainstay means the chief support.

• Correct answer - chief support: it has the same meaning as Mainstay.
• conclusion: an ending or final decision - wrong, it does not mean the same as Mainstay.
• strong resistance: powerful opposition - wrong, it does not mean the same as Mainstay.
• stimulant: something that increases activity - wrong, it does not mean the same as Mainstay.