A.I. Explanation:

Option 1: "Lighting his surroundings was a major concern for the primitive man."

Explanation: The text indicates that primitive man was more focused on fire for warmth and cooking rather than for illumination. Therefore, this statement contradicts the main idea of the text.

Option 2: "Primitive man used to soften his food by heating it."

Explanation: The text mentions that primitive man was concerned with fire as a means of cooking food, which implies that he used heat to soften food. This aligns with the main idea of the text regarding the practical uses of fire.

Option 3: "Torch was discovered more by accident than by design."

Explanation: The text states that the discovery of the firebrand, which led to the development of the torch, was probably incidental. This supports the idea that the torch was discovered by accident rather than through intentional design.

Option 4: "Preserving fire was not a major concern for the primitive man."

Explanation: The text clearly states that primitive man had to preserve fire and carried a firebrand with him on journeys, indicating that preserving fire was indeed a major concern.

Option 5: "Some of the primitive lamp designs survived for long through the ages."

Explanation: The text mentions that lamps made of hollowed stones or sea-shells have persisted in identical form up to quite recent times, supporting the idea that some primitive lamp designs have survived through the ages.