What is the working and reactive power in this circuit
If you correctly calculated the impedance then:
\$I=\dfrac{U}{Z}\$ or  simply  \$|I|=\dfrac{U}{|Z|}\$.

\$Z=\sqrt{R^2+X^2}= \sqrt{1+4}\$ then \$P=I^2\cdot R\$ and \$Q=I^2\cdot X\$ 

Or yet simpler: 

\$P=\dfrac{U^2\cdot R}{R^2+X^2}\$ and so on

Znači D.