I'm pretty sure the answer is D
        
             
        
        
        
The planets closest to the star are rocky planets formed by elements with high melting points. Moreover, planets far away are gaseous planets and they are composed of elements with lower melting points.
<h3>Rocky planets and gaseous planets</h3>
The rocky planets consist of silicate rocks and/or metals, whereas gaseous planets are mainly composed of hydrogen and helium.
The rocky planets of the solar system include planets closest to the sun, i.e., Mercury, Venus, the Earth, and Mars.
The gaseous planets of the solar system include faraway planets, i.e., Jupiter, Saturn, Uranus, and Neptune.
Learn more about rocky planets here:
brainly.com/question/17428928
 
        
             
        
        
        
A) One species always outcompetes the other until only one species remains.
        
             
        
        
        
The correct answer is the homeostasis.
 A plant may close and open its stomata to prevent excess water loss and maintain homeostasis.
Homeostasis is termed as the tendency of organisms to maintain and automatic regulation of their internal environment to be in a stable condition. 
We say that the plant is in stable condition when the fluid balance and body temperature are being kept in to a pre-set limits which include calcium ions, potassium, sodium and PH of extracellular fluid.
The natural resistance which changes the optimal condition brings about homeostasis.