<span>The hormone which is being produced under a water-deficit condition which triggers a drought response is known as Abscisic Acid or ABA. 
Abscisic acid is termed as a plant hormone. The main functions in the development of plants include 
1. Stomatal closure. 
2. Control of organ size. 
3. Bud dormancy. 
It responds to environmental stresses in plants, which include heat stress, freezing tolerance, cold tolerance, soil salinity, and drought.</span>
        
                    
             
        
        
        
Answer:
contraction and relaxation of the heart
Explanation:
 
        
             
        
        
        
The correct option is (d) The early solar system had large amounts of water; so, the oldest objects in the solar system should also be abundant in water. 
The statement that answers the scientific questions in the form of scientific data that supports the claim is called a scientific claim. There is need for the justification of the claim. The scientific claim here is The early solar system had large amounts of water and the justification to the claim is water is found in all the primitive bodies like the comets and the asteroids and in many dwarf planets like ceres. There are many evidences that shows that there are abundant amount of water in our solar system.
 
        
                    
             
        
        
        
The earths core is D.hotter than both the crust and mantle