At the time of death, which of the following occurs?

• A. Heart stops; skin tight and grey; cells start to die; muscles relax
• B. Lungs hyperinflate and the heart speeds up
• C. Body temperature immediately falls to 0°C
• D. Rigor mortis occurs instantly

Answer: (A)

When death occurs, circulation and respiration stop, so the heart no longer pumps and tissues are deprived of oxygen. That loss of blood flow leads to pallor and a grayish skin tone as perfusion ceases, and cells begin to die from the lack of oxygen. Muscles relax because there is no neural input or ATP maintaining contraction once life ends. Rigor mortis does not happen instantly; it appears later, after a few hours, as muscles become stiff due to the chemical changes after death. The other statements describe changes that do not occur at the moment of death: lungs would not suddenly hyperinflate and the heart would not speed up; body temperature does not drop to 0°C immediately.