glucose, carbon dioxide, and water.
all the options are correct.
1. new ways to preserve and transport blood for blood transfusions were discovered.
2. blood transfusion safety was improved.
3. scientists discovered that elements of blood could be separated by centrifuge.
4. scientists discovered that plasma could be preserved by freezing.
karl landsteiner was the man who discovered some of the human blood types in 1900 and 1901 at the university of vienna.