Answer:
Selective Optimization With Selection.
Explanation:
It is known that this theory was widely known from 1980s and was postulated by a man called Baltes. Baltes here argued that as individuals advance through life they are increasingly faced by age related deficits which place limits on their cognitive and behavioral resources. Tackling these limits placed on domains, individuals will begin to invest resources into particular styles and behaviors that are deemed adaptive to the new constraints. 
 
        
             
        
        
        
Lasts are used for photosynthesis .
They have a double membrane around them.
The space inside is called the stroma. The space may contain starch grains and lipid bodies.
In the stroma are structures called thylakoids.
The thylakoids are stacked to form structures called grana.
The grana contain the pigment chlorophyll along with some secondary pigments.