Three of these processes normally consume oxygen. which process produces oxygen?
a)
combustion
b)
respiration in animals
c)
photosynthesis in plants
d)
operation of an acetylene torch

Answer – C. (photosynthesis in plants)
 Out of the four options given, the only process which produces oxygen is photosynthesis in plants. The other three processes given in the options: Combustion, Respiration in animals, and operation of an acetylene torch normally consume oxygen.

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