Answer: c. 21,000
Explanation:
Since, by the given diagram,
The approximate number of security guard job opening = 39,000
And, the approximate number of pharmacy technicians job opening = 18,000
Hence, the difference of the number of security guard job opening and the number of pharmacy technicians job opening = 39,000 - 18,000 = 21,000
Thus, the job openings for security guards is approximately 21000 greater than that of pharmacy technicians.
⇒ Option C is correct.