Which of the following countries has largest number of Islands?

In September 2009, Mining group Petra Diamonds has discovered a 507.55-carat white diamond at South Africa’s Cullinan mine, one of the largest high-quality rough diamonds ever found, and is ranked as one of the 20 biggest high-quality diamonds ever discovered.

Berlin, capital, and chief urban center of Germany. Berlin was founded on the River Spree. It has now expanded to include a stretch of the River Havel, of which the Spree is a tributary.