At 10-12% oxygen, which symptoms are listed?

At 10-12% oxygen, which symptoms are listed?

• A. Respiratory rate increases
• B. Unconsciousness
• C. Dizziness, headache, nausea, fatigue
• D. Coma

Answer: (C)

When oxygen levels in the air are very low (around 10-12%), the body first shows signs of hypoxia that reflect reduced oxygen delivery to the brain and tissues. The most common early symptoms are dizziness or light-headedness, headache, nausea, and fatigue. These indicate the body's initial attempts to cope with less oxygen. As hypoxia worsens, more severe signs can appear, such as unconsciousness or coma, and sometimes an increased respiratory rate as the body tries to compensate. So the listed symptoms correspond to the initial, early response to significant oxygen deficiency, which is why they’re the best match for this level.

When oxygen levels in the air are very low (around 10-12%), the body first shows signs of hypoxia that reflect reduced oxygen delivery to the brain and tissues. The most common early symptoms are dizziness or light-headedness, headache, nausea, and fatigue. These indicate the body's initial attempts to cope with less oxygen. As hypoxia worsens, more severe signs can appear, such as unconsciousness or coma, and sometimes an increased respiratory rate as the body tries to compensate. So the listed symptoms correspond to the initial, early response to significant oxygen deficiency, which is why they’re the best match for this level.