The correct answer is option C: someone diagnosed with smallpox.
The person that would have been most grateful for the work of 19th-century scientist Edward Jenner, would be someone diagnosed with smallpox because Jenner was who discovered the first vaccine against the smallpox virus. Moreover, this disease that was widely spread in the 18th century and killed many people.
The correct answer is b. - tsunamis.
Tsunami is a Japanese word meaning harbor wave.
Tsunamis are giant waves caused by earthquakes or volcanic eruptions under the sea. This usually happens deep out in the ocean. The earth movement causes a displacement of water in the form of a large ripple which begins to move inland at tremendous speed.
There is no dramatic increase in height of the wave, but as it moves toward the coast, it builds up to a higher and higher height as the ocean becomes shallower and shallower till when it makes land fall, the wave may be dozens of feet high.
Answer: Outer core
Reason: As Earth spins on its axis, the iron inside the liquid outer core moves around. The movement causes powerful electric currents to develop in the liquid iron itself.