Which of the following is a common property of the light-emitting compound in fireflies?

The light-emitting compound in fireflies is known as luciferin, which is a crucial component of the bioluminescence process. This compound undergoes a chemical reaction in the presence of oxygen, facilitated by the enzyme luciferase. When luciferin oxidizes, it releases energy in the form of light, which is the phenomenon we observe as the glowing effect in fireflies.

Each of the other compounds mentioned has different roles and properties, but they are not associated with the bioluminescence seen in fireflies. Chlorophyll is the green pigment found in plants that is essential for photosynthesis, carotene is a pigment responsible for the orange color in many fruits and vegetables and plays a role in photosynthesis as well, while riboflavin, also known as vitamin B2, serves as a coenzyme in metabolic processes. None of these compounds are involved in the light-emitting reaction specific to fireflies, making luciferin the correct choice.