Table 2The Figures in the Table Below Are Taken from the the Statistics

Table 2.The figures in the table below are taken from the statistics office in a fictional country called Exland.
$\begin{array}{llcc} \text {Number of workers employed} &8,400\\ \text {Frictional unemployment} &250\\ \text {Structural unemployment} &350\\ \text {Cyclical unemployment} &600\\ \text {Discouraged workers} &400\\ \text {Adult population} &12,000\\\end{array}$

-Refer to Table 2.How large is the labour force in Exland?

A) 7,550.
B) 8,000.
C) 8,400.
D) 9,600.