In a decay sequence, the term for the original element before any decay is called the

In a decay sequence, the term for the original element before any decay is called the

• A. Daughter material
• B. Parent material
• C. Decay product
• D. Isotope

Answer: (B)

In a decay sequence, the starting nucleus is called the parent. It’s the original element that undergoes decay to form the next species, the daughter (the decay product). The term “isotope” just means variants of the same element, not the starting point in a decay chain. “Daughter material” isn’t standard terminology, and “decay product” describes what you obtain after the decay, not what you started with. So the best fit for the original element before any decay is the parent material.

In a decay sequence, the starting nucleus is called the parent. It’s the original element that undergoes decay to form the next species, the daughter (the decay product). The term “isotope” just means variants of the same element, not the starting point in a decay chain. “Daughter material” isn’t standard terminology, and “decay product” describes what you obtain after the decay, not what you started with. So the best fit for the original element before any decay is the parent material.