Which graph indicates that increasing exposure to cigarette smoke increases the risk of emphysema? justify your reasoning in terms of the behavior of the dependent and independent variables.
a) b: the dependent variable remains constant.
b) d; the independent variable remains constant.
c) c; as the independent variable increases, the dependent variable increases.
d) a; as the independent variable increases, the dependent variable decreases.
in the picture

Aresearch study is studying the effects of a new drug for osteoporosis alzheimer's disease (ad) for women above the age of 65 years. a group of individuals with osteoporosis is randomized into two groups. one group is treated conventionally, and the second group is treated with the new medication. assessments are made at 3, 6, 12, 36, and 48 months. the conventionally treated group is assessed for ad using a serum blood test, and the treatment group is assessed for ad using a pet radiotracer that binds to beta-amyloid plaques. in comparing these 2 trial arms, the authors of the study may encounter which type of bias? a. selection bias on the risk of developing b. measurement bias c. confounding bias d. recall bias e. lead-time bias