Which word is defined as 'marked by stubborn determination and persistent effort'?

• A. Dogged
• B. Easily discouraged
• C. Polite and courteous
• D. Quick to change opinions

Answer: (A)

The concept tested here is recognizing a word that conveys steadfast perseverance and stubborn determination. Dogged describes someone who keeps going with firm persistence, even when obstacles arise, and carries a stubborn commitment to see a goal through. This fits the definition of marked by stubborn determination and persistent effort because it emphasizes both tenacity and a refusal to give up.

Easily discouraged signals the opposite—giving up when faced with difficulty—so it doesn’t match. Polite and courteous describes manners rather than perseverance. Quick to change opinions points to instability and lack of resolve, not the determined, steady effort implied by dogged.