One of the common symptoms observed in people infected with Dengue fever is:

The correct option is C

Significant decrease in platelets count

Dengue virus, the main cause of dengue fever induces bone marrow suppression. Since bone marrow is the manufacturing centre of blood cells its suppression causes deficiency of blood cells leading to low platelet count. Anaemia and spontaneous severe bleeding are the other resultant factors of bone marrow suppression.