A _____ is used in submarines to monitor the surface of water.

آبدوزوں میں پانی کی سطح کی نگرانی کے لیے ایک _____ استعمال کیا جاتا ہے۔

Periscope

Telescope

Kaleidoscope

Binoculars

A Periscope is an optical instrument used to observe objects that are not in direct line of sight.
Such as monitoring the surface of the water from a submarine.