Endoscope is an instrument used to detect the ulcers in the stomach has a long narrow tube (with a small glowing bulb at one en4⃣ which is inserted in to the stomach through the mouth contains.

A) small current carrying wire B) a narrow tube containing water C) optical fibre D) which is inserted in to the stomach through the mouth contains.? 1⃣ small current carrying wire 2⃣ a narrow tube containing water 3⃣ optical fibre