The correct option is D Lymphocytes
Human immunodeficiency virus (HIV) infects the cells of the immune system particular T helper lymphocytes (WBC) or T-cells, which are crucial to the immune system and immune response. In these cells, HIV uses the protein CD4, present on the surface of the cell, to attach itself and copy itself over and over by reverse transcription, increasing its number reduces the CD4+ T-cells. Thus, the correct answer is option D.