In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.
A brain and nervous system that are poorly developed or insufficiently nourished means low grade of_____ constructed or wrongly adjusted motor means loss of power in applying the electric current to its work. We will counterparts of_______other, each performing activities which correspond to activities in the other, is concerned, and each getting its____ nourished means low grade of____ in our mental processes, just as a poorly , look upon the mind and the brain as inextricably bound together at least so far as this life . by its union with the other. This view will lend interest to a brief study of the brain and nervous system.
nourished means low grade of ................... in our mental processes.

Options

A. efficiently
B. efficiencies
C. efficiency
D. efficient

Answer

C