The correct answer is A.
Toxins and various pollutants increase in concentration through the food chain in a process called biomagnification. This means that the organisms on the top of the food chain, like the herring gull, have many times greater concentration of toxins than the lower food chain level organisms because they prey on lower food chain level organisms. If a herring gull ears 100 herrings, it will have a 100x times greater concentration of toxins in its body than a herring.
Answer: in order from small intestine to the rectum: 1, 4, 2 and 3.
Explanation: Ascending colon; the colic valve(the ileocecal valve) is located at the bottom of the ascending colon. At the top of the ascending colon, the colon bends to the left, forming the right colic flexure called the hepatic flexure. The transverse colon begins after this flexure.
The transverse colon; is the longest and most movable part of the colon which runs across the abdomen from the ascending colon at the right colic flexure with a downward convexity to the descending colon, here it curves abruptly on itself under the lower end of the spleen to form left colic flexure called the splenic flexure.
Descending colon; it start from the splenic flexure to the beginning of the sigmoid colon. The descending colon stores the remnant of digested food that will be deposited into the rectum.
Sigmoid colon; also known as pelvic colo is the closest to the rectum, it is a passage by which digested food move into the rectum.
Atmosphere of the early earth + lighting = paleolightning
