Which of the following statements is correct pertaining to theisomers of curcumin, the bright yellow plant extract that MarcoPolo wrote about in 1280 AD?

a. one of the tautomers (the ketone) is lethal if ingested

b. one of the tautomers ) the nol) has anti-oxidantproperties

c. neither one of the tautomers have anti-oxidant properties

d. both the keto and enol tautomers have anti-oxidantproperties