The surprisingly abundant life of the Indian Ocean is confined
to the upper layers; the deeper and especially the bottom waters
are devoid
of oxygen and are often permeated with hydrogen
sulphide.
- The sentence gives the information about
a) the life of the people near the Indian Ocean.
b) the reason why life exists in particular water layers.
c) the reason why oxygen is found in the bottom layers.
d) the reason why hydrogen sulphide is found in the bottom layers.
- The bottom waters of the Indian Ocean
a) have no oxygen
b) have large amounts of oxygen
c) have no hydrogen sulphide.
d) contain oxygen and hydrogen sulphide.