Which Spanish national park in the Pyrenees is home to Europe's largest population of the rare Pyrenean desman, a semi-aquatic mammal related to moles?

• A Ordesa y Monte Perdido
• B Aiguestortes i Estany de Sant Maurici ✓
• C Picos de Europa
• D Sierra de Guadarrama

The Pyrenean desman (Galemys pyrenaicus) is an endangered aquatic mammal found in clean mountain streams of the Pyrenees and northern Spain.