Answer:
Abiotic is basically a non living factor so the answer is 
D. Sunlight, temperature , conductivity, dissolved oxygen.
All other options contain one biotic or living factor like algae, star fish and crabs these aren't Abiotic.
 
        
             
        
        
        
Answer:
Producers are always at the beginning of a food chain. Producers begin every food chain because they can make their own food.
 
        
             
        
        
        
B.) Atp and NADPH are produced from the calvin cycle
        
             
        
        
        
Answer:
The thoracic cavity is "Superior" to the abdominopelvic cavity. Superior ... If an incision cuts the heart into right and left parts, a "Sagittal" plane of section was used
Explanation: 
The thoracic cavity is mainly located in the chest region which also have neck and the diaphragm in it. In the thoracic cage the thoracic organs are safely placed. The thoracic cavity lies above the abdominopelvic region. The sagittal plane is the vertical plane which runs from the front to back of the body. The sagittal plane helps in splitting of two equal halves like the left and right one.