Answer:
The correct answer is option A-"They release energy".
Explanation:
The phenomenon of radioactive decay, also known as radioactivity or nuclear radiation, occurs when an unstable atomic nucleus emits radiation and loses energy and mass in the process. The elements during radioactive decay release energy and mass trying to reach a stable form. The material that has the unstable nucleus is considered radioactive.
The correct answer is Metal.
Sound waves are vibrations which need medium to propagate. Higher the density of medium, the sound travels fastest. Sound travels fastest in solid than liquid and gas. Therefore, in this question sound will travel faster in metal because metal has higher density than air and water and it will not travel in vacuum as sound needs medium to travel.
Organisms with the most favourable traits will increase their success rate in a particular environment. Organisms with favorable traits are more likely to reproduce and pass on their traits than organisms without favorable traits, allowing it to survive.
