Which of the following statements is true? More than 50 chemicals in tobacco are known to cause cancer.
Eating disorders are more common in boys than in girls.
Liver scarring is a serious health issue caused by bulimia.
Smoking causes lung cancer, but it does not harm other body organs.

What link in the chain of transmission is described in the paragraph? sarah has been eating and sleeping poorly. she was just diagnosed with pneumonia. tests showed the illness was caused by streptococcus pneumoniae. in the chain of transmission, sarah is the (blank) , and streptococcus pneumonia is the (blank).