Which of the following indicates a serious sign of shock?

All of the options listed—lethargy, confusion, and cool clammy skin—are indeed serious indicators of shock.

Lethargy signifies decreased alertness and energy, which can occur due to inadequate blood flow and oxygen delivery to the brain. This reduction in mental responsiveness is a concern during shock.

Confusion also reflects impaired brain function caused by insufficient perfusion. Confusion can be a manifestation of diminished blood supply to vital organs, particularly the brain, reflecting the seriousness of a patient’s condition.

Cool clammy skin is another hallmark symptom, as peripheral vasoconstriction occurs in shock to preserve blood for vital organs. This effect results in skin feeling cool and damp as blood flow is redirected away from the extremities.

Since each of these signs illustrates a significant and worsening condition, recognizing them collectively underscores the critical nature of shock and the need for immediate medical intervention.