Answer:
A. The complete journey of one object around another. 
Explanation:
Revolution can be defined as the complete journey of one object around another.
This ultimately implies that, the complete movement (motion) of the Earth along a path (an orbit) around the Sun or the Moon around the Earth is referred to as revolution.
Basically, it takes the Earth 365 1/4 days to completely move around the Sun.
Additionally, the earth rotation and revolution gives rise to the following phenomenon;
a. Day and night. 
b. Seasons such as summer, winter, autumn, etc. 
c. Creation of heat zones and ocean currents 
 
        
             
        
        
        
The answer you are looking for is under option A
        
             
        
        
        
Answer:
B
Explanation:
It is because burning fossil fuels release sulfur dioxide which causes acid rain.
 
        
                    
             
        
        
        
an animal that eats both plants and animals is an omnivore.
        
                    
             
        
        
        
Answer:
D) the steady, clocklike decay of certain radioactive isotopes over time.
Explanation:
Geologists use radiometric dating to estimate how long ago rocks formed, and to infer the ages of fossils contained within those rocks. 
For example, when rocks are formed, such as igneous rocks (formed when molten rocks cools), certain radioactive atoms are trapped inside the rocks during this formation process. Then these radioactive atoms decay over time.
The age of the rock can be estimated by comparing the occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
From the options;
A) this is about the formation of the radioactive molecules and not about radiometric dating
B) this is radiocarbon dating (cabon dating/carbon-14 dating)
C) the <em>assumption </em>is wrong since the radioactive isotopes decays not accumulate.
D) the corect option as I explained earlier.