Read the passage I carefully and answer the questions that follow.

PASSAGE 1

Primitive ma was probably more concerned with fire as a source of warmth and as a means of cooking food than as a source off light. before he discovered less laborious ways of making fire, he had to preserve it and whenever he is sent on a journey, he carried a firebrand with him, His discovery that the firebrand, from which the touch may well have developed, could be used for illumination was probably incidental to the primary purpose of preserving a flame. Lamps, too, probably developed by incident. Early man may have had his first conception of a lamp while watching a twig or fibre burning in the molten fat dropped from roasting carcass. All he had to do was to fashion a vessel to contain fat and float a lighted reed in it. Such lamps, which were made of hollowed sea Shells, have persisted in identical form up to quite recent times.