What discovery was made by alvin?

a. over 4000 new species of marine life

b. hydrothermal vents

c. the aqualung

d. the temperature of different parts of the ocean

Alvin was a deep sea vehicle which was used to explore the depths of the ocean. It sunk but was recovered and recommissioned in 1973 after which it discovered black smokers, a special type of hydrothermal vent which produces super heated water with a highly acidic pH. Thus, the answer is B.