To write 45,812 in words, break it into place-value groups.
• 45 thousands → "Forty-five thousand"
• 812 → "eight hundred and twelve"
• Combine with a comma: "Forty-five thousand, eight hundred and twelve"
Option A is wrong (uses "hundred and fifty-eight thousand" — that would be 458,000).
Option B is wrong ("forty-five hundred" = 4,500, not 45,000).
Option C is wrong (inserts "and fifty" inside the hundred — means 450,000+).
Option D matches our breakdown exactly.
Final Answer: D: Forty-five thousand, eight hundred and twelve