One junction of a certain thermoelectric couple is at a fixed temperature \[{{T}_{r}}\] and the other junction is at temperature T. The thermo electromotive force for this is expressed by \[E=K(T-{{T}_{r}})\left[ {{T}_{0}}-\frac{1}{2}(T+{{T}_{r}}) \right]\]. At temperature \[T=\frac{1}{2}{{T}_{0}}\], the thermoelectric power is [MP PMT 1994]

• A.                    \[\frac{1}{2}K{{T}_{0}}\]  
• B.                    \[K{{T}_{0}}\]
• C.                    \[\frac{1}{2}KT_{0}^{2}\]
• D.                    \[\frac{1}{2}K{{({{T}_{0}}-{{T}_{r}})}^{2}}\]