the causative organism of dengue fever is : a.) fungus b.) bacteria c.) protozoa d.) virus

which of the following elements obtained from the sea algae : a.) argon b.) sulphur c.) vanadium d.) iodine

heart attack occurs due to : a.) bacterial attack on the heart b.) stopping of heart beat c.) lack of blood supply to the heart d.) impairment of heart’s working due to the unknown reasons

who discovered the cholera-bacillus : a.) louis pasteur b.) ronald ross c.) robert koch d.) joseph lister

pregnant women usually become deficient in : a.) sodium & calcium b.) iron & sodium c.) calcium & iron d.) magnesium & iron

yellow fever is transmitted by : a.) aedes b.) anopheles c.) house-fly d.) culex

the color of human skin is produced by : a.) hemoglobin b.) insulin c.) adrenaline d.) melanin