It is body composition! Np Welcome :P
its to hard but you can answer this
A pack of wolves move into a forest
The controlled experiments are performed by the scientists, when they want to study the changes in the sample on changing a single variable. So, the correct answer is option (b).
In case, all variables are kept same, no changes would be observed in the experiment sample. A controlled experiment can be performed on living thing as well as non living. But, controlled experiment cannot be performed on the things which are influenced by a lot of variables, as they cannot create realistic results. So, the option (a), (c), and (d) are incorrect.
Answer:
Researchers also found that the longer a male's tail feathers, the faster he was able to shake them. This effort would require more muscular strength, and might be a powerful signal of fitness to the females.
Explanation:
