Problem: Two regions of the same country had very different climates because of the different landscapes. East region had an alpine landscape, was situated in the mountains. North region was flat and located at sea level. Which region didn't have a warmer climate?

A: East

Problem: Two biologists studied different living creatures. Matt studied protozoa, while his friend Greg studied nematodes and insects. Which friend studied less about herbivore protozoa?

A: Greg

Problem: Keith is a doctor in a local hospital. Today, he is seeing three patients, patient A, patient B, and patient C. Patient A has been suffering from hepatitis B all his life; patient B is recovering from hepatitis B on his own; and patient C doesn't have hepatitis B. Keith would now compare the symptoms of these patients. Which patient's symptoms would less likely include vomiting, patient A or patient C?

A: patient C

Problem: Doctors studied two groups of individuals: group O with people over 65, and group S with people under 65 years old. They published the results in a magazine. Which group had fewer people with decreased stamina?

A:
group S