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‘Lub-dup’ sound is produced due to action of

Options

  1. ALarge intestine
  2. BLungs
  3. CHeart
  4. DOesophagus

Correct answer

C. Heart

Step-by-step solution

In healthy adults, there are two normal heart sounds often described as a lub and a dub (or dup) that occur in sequence with each heartbeat. These are the first heart sound (S1) and second heart sound (S2) produced by the closing of the AV valves and semilunar valves, respectively.

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