Correct Answer: Pinnacle

Solution : The fourth option is correct.

In the given sentence, apex means the highest point or pinnacle. Pinnacle , as a synonym, also signifies the highest level or peak. Both words describe the director's position as the highest authority or position within the managing committee.

The meanings of the other options are as follows:

• Core : It is the central or most important part of something, the essence, or the centre around which other parts are grouped or developed.
• Bottom : It is the lowest part or point, opposite of the top; it can also refer to the underlying or fundamental basis of something.
• Corner : It is a place or angle where two or more sides or edges meet; it can also refer to a position of advantage or control.