Correct answer is (a) 5.43 μF
For explanation: The 2 μF capacitor is in parallel with 1 μF capacitor and this combination is in series with 0.5 μF.
Hence, C1 = \(\frac{0.5(2+1)}{0.5+2+1}\)
= \(\frac{1.5}{3.5}\) = 0.43
Now, C1 is in parallel with the 5 μF capacitor.
∴ CEQ = 0.43 + 5 = 5.43 μF.