The main constituent of hemoglobin is? A. Chlorine B. Iron C. Calcium D. None of these Right Answer: Iron Share : February 19, 2018 Asghar Khan Everyday Science Total 0 Votes: 0 0 Tell us how can we improve this Mcqs? Captcha: + = Verify Human or Spambot ? Related Mcqs Check Below -The sky appears blue because the earth’s atmosphere?Biosensor is used to measure?X-rays were discovered by?