Explanation: Fiber optic cables transmit data using light, often at power levels that can cause significant harm to the eye. The critical danger highlighted in option B is that these signals frequently operate in the infrared (IR) spectrum, which is invisible to the human eye. Since you cannot see the light, you won't realize you are exposed until damage occurs. The eye's lens focuses this invisible, powerful light directly onto the retina, where it can cause thermal burns and permanent vision damage. Option A is incorrect because while extremely high-power lasers can affect skin, the retina is far more vulnerable to focused light. Option C describes a handling issue, not a direct safety hazard from looking into the cable. Option D is incorrect because the signal is typically infrared and *invisible*, not visible red. The invisibility is precisely what makes it so dangerous.