Which flight hazard is caused by natural phenomena affecting visibility?

Solar glare is a flight hazard caused by natural phenomena that can severely impair visibility for pilots. When sunlight reflects off surfaces such as water, snow, or other bright surfaces, it can create intense brightness that obstructs a pilot's ability to see the runway or other critical visual cues needed for safe flight operations. This glare can be particularly challenging during takeoff or landing phases.

The other options, while relevant hazards, do not primarily stem from natural phenomena affecting visibility. Bird strikes involve collision with wildlife, lasers refer to light sources used intentionally or accidentally near aircraft, and nerve agents are toxic chemical substances that pose a different type of risk related to safety but do not directly impact visibility during flight. Thus, solar glare is the most relevant choice when considering visibility hazards caused by natural phenomena.