Answer:
All the ones listed below are true
Potassium, carbon, sulfur, hydrogen, oxygen, nitrogen, calcium, magnesium, sodium, phosphorus, iron, zinc, silicon, fluorine, boron, cobalt, manganese, chromium, and some others
Explanation:
1) The male frogs croak to attract mates. They can also visually attract females by displaying vibrant colors. They compete by comparing who calls louder
2) This aids in survival because this ensures that only healthy frogs get to pass down their genes. Unhealthy frogs will not be selected by females. This is called sexual dimorphism
3) The hummingbird displays its impressive tails which they move around to attract females. They may perform aggressive movements against other competing males.
4) These strategies are very important to maintain a diverse and healthy population in a community of animals.
The answer is C. The brain stem controls blood circulation.
