Ответ:

  1. c. There are many recipes, so the origins are difficult to settle definitively.
  2. b. Calling someone’s borsch “not the real thing” is impolite.
  3. c. Beetroot gives borsch its characteristic colour.
  4. c. Beetroot is the main ingredient.
  5. a. It is impolite to criticize someone’s food.
  6. a. The sentence identifies the lack of smetana as the distinguishing feature.
  7. b. The ingredients take time to mature.

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