Ddt was widely used as a pesticide for 20 years. its use was banned after studies showed severe side effects were evident in humans, the environment, and animals as a result of ddt. which reason best explains why the side effects of ddt were so harmful? a. ddt kills insects and other pests. b. ddt decomposes. c. ddt was genetically engineered. d. ddt bioaccumulates.

d. DDT bioaccumulates

Explanation: Bioaccumulation is the entry of pollutants such as metals into a food chain. Substances such as perchlorinated biphenyls (PCBs), (DDT) are potentially dangerous over a period of time as it accumulates. DDT concentration is calculated in parts per million.

Biomagnification on the other hand is the build up of toxins in a food chain. An increase in the trophic level in a food chain results to an increase in the amount of toxic build up.

the limb fractures are among the most common fractures. open fractures are comparatively more dangerous. the injury patterns are dependent on many factors, such as the age of the person, and mechanism of the injury. the closed fractures of the limbs if left untreated may lead to a significant amount of the blood loss, which may be life-threatening for the person. approximately 1000-1500 ml of blood is lost in the close fracture of the femur, and 500-1000 ml of blood is lost in the closed fracture of lower part of the limbs.