Final answer:
Lymphocytosis is the correct term for a slight increase in the number of lymphocytes, which can be a sign of viral infections or some cancers.
Step-by-step explanation:
The question 'A slight increase in numbers of lymphocytes' asks you to identify the correct term from the provided options. The appropriate term in this case is lymphocytosis, which refers to an increase in the number of lymphocytes, a type of white blood cell. Lymphocytosis can be indicative of various conditions, including viral infections and certain types of cancer. Abnormally low lymphocyte counts, on the other hand, would be described as lymphocytopenia and can occur due to chronic illness or immunosuppression, such as that caused by HIV infection or treatments involving steroids. Other terms listed, such as lymphoma and lymphopoiesis, represent different concepts: lymphoma is a cancer of the lymphatic system and lymphopoiesis is the process of lymphocyte production.