Blood

Step 1: Understanding lymphocytes.
Lymphocytes are a type of white blood cell (WBC) involved in the immune response. They include T-cells, B-cells, and natural killer (NK) cells, which play roles in adaptive and innate immunity.

Step 2: Size range of lymphocytes.
Lymphocytes typically range in size from 10-15 micrometers. Larger lymphocytes are generally activated or immature forms, while smaller ones are resting lymphocytes.

Step 3: Explanation of options.
Option (A): Incorrect. The size range of 5-10 micrometers is too small for most lymphocytes.

Option (B): Correct. Lymphocytes typically range between 10-15 micrometers.

Option (C): Incorrect. 15-20 micrometers is too large for most lymphocytes.

Option (D): Incorrect. Lymphocytes do not reach 20-25 micrometers in size.