What characterizes the plants of the second green revolution? 

A)  They are adapted to drought. 
B)  They are giant varieties. 
C)  They are slow growing. 
D)  They are high-yield varieties.

The plants of the second green revolution are characterized by being high-yield varieties, which means they produce a larger amount of crops per acre. This is achieved through the use of advanced seed breeding techniques and biotechnology. The other options (A, B, and C) do not accurately describe the characteristics of the plants of the second green revolution.