Which of the following WBCs are associated with allergic reactions?

Match the following columns and select the correct option.

The haemocytometer is a thickened glass slide with small chamber of grids cut into the glass and is used to count cells. Each chamber has a fixed volume and is etched into nine large squares (see figure, $P$ to $X$ ), each measuring $1\mathrm{mm}\times 1\mathrm{mm}$ and $0.1\mathrm{mm}$ deep. Each large corner squares $(P,R,V$ and $X)$ contain $16$ small squares. With a coverslip in place, each of these small squares represents a volume of $0.1{\mathrm{mm}}^3$ $\left(1.0{\mathrm{mm}}^2\right.$ area $\times 0.1\mathrm{mm}$ depth ) or ${10}^{-4}{\mathrm{cm}}^3$. The number of cells counted in $4$ large corner squares was $400$, with the conversion factor as $1000.$

$\mathrm{Number} \mathrm{of} \mathrm{cells}per\mathrm{ml}=\frac{ \mathrm{Number} \mathrm{of} \mathrm{cells} \mathrm{counted} }{ \mathrm{Large} \mathrm{squares} \mathrm{counted} }\times \mathrm{Dilution} \mathrm{factor}$

Given this information, calculate the total number of cells suspended in a volume of $5\mathrm{ml}$, considering that the cells were diluted $1: 2$ before counting.

Which one of the following is incorrect regarding WBCs?

(a) Monocytes migrate from the bloodstream to other tissues and differentiate into tissue-resident macrophages, Kupffer cells in the liver.

(b) Eosinophils modulate allergic inflammatory responses.

(c) Basophils release histamine for inflammatory response.

(d) Natural killer cells are a type of phagocytic erythrocytes.