In the Section "Investigating Life: the Hidden Cost of Hygiene",how

In the section "Investigating Life: The Hidden Cost of Hygiene",how can the scientists further test whether flatworms can moderate the immune system?

A) Expose white blood cells to flatworm antigens and measure interleukin concentrations.
B) Expose white blood cells to dust mite antigens and measure interleukin concentrations.
C) Expose white blood cells to flatworm antigens and measure histamine concentrations.
D) Expose white blood cells to dust mite antigens and measure histamine concentrations.
E) Infect children with flatworms and look at their number of white blood cells