Step 1: Identify the sovereign debt crisis context.
The European sovereign debt crisis (2009-2010s) primarily affected countries with high public debt and deficits, notably in the Eurozone.
Step 2: Match with affected countries.
The most affected countries were Spain, Greece, Iceland, and Portugal due to severe financial instability and bailouts.
Step 3: Eliminate distractors.
(A) Includes Germany, which was stable.
(B) Includes Czech Republic, not heavily impacted.
(C) Includes Switzerland, which remained stable.
(E) Includes Germany and U.K., which were not primary crisis zones.
Therefore: The correct answer is (D). \[
\boxed{\text{D}}
\]