Question

For seeing objects at the surface of water from a submarine under water, the instrument used is
A.periscope
B.telescope
C.kaleidoscope
D.spectroscope

Answer 1

periscope is required

Answer 2

The answer is periscope.

When a submarine have to locate objects at the surface then they depend on periscope.

It can be through or around the object that made it visible.

In addition to this, it avoids any sort of direct sight line from the point of observation to the object being observed.