A group of students was designing an experiment to test the effect of smoking on grass frogs. They hypothesized that keeping the frogs in a smoke-filled environment for defined periods would result in the animals developing lung cancer. However, when they searched for previously published information to shore up their hypothesis, they discovered they were quite wrong in their original assessment. Even though they were never going to go ahead with their experiment (so as not to harm frogs needlessly), they knew that a more likely outcome of putting carcinogens in the air would be the development of ___.
a. diminished absorption of oxygen
b. tracheal tube abnormalities
c. skin cancer.
d. the amphibian equivalent of hypertension.
e. gill abnormalities in the next generation of tadpoles