This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
A laboratory analysis report of a specific fraction of a patient's lymphocytes the following:

HLA, Band C+,PHA+, CD3-, CD16+, CD11a/ CD18+, CD56+, and in vitro blastogenesis with IL12 What are the lymphocytes this set describes? 
Select and explain. 
A. B lymphocytes, B. Cytotoxic T lymphocytes, C. Natural killer cells, D. T helper 1 subset
C: Natural killer cells
Answer: C: Natural killer cells 
Explanation: NK cells do not express a cell surface TCRlCD3 complex and are CD4-. About half of human NK cells are CD8+. Also, most NK cells express an Fe IgG receptor, known as CDI6, and CD56, a neural cell adhesion molecule variant. NK cells are generally CD16+, CD56+, and CD3-, which contrasts them with I cells which are CD3+, CDl6-, and CD56