Immunoglobulins that attach to and sensitize mast cells and basophils are

IgE

Explanation:

Immunoglobulins can be described as antibodies that are found in blood and other bodily fluids of humans and other vertebrate animals. And their major function is that they help identify and destroy foreign substances such as microbes such as bacteria and protozoan parasites.

They are known to be produced by produced by plasma cells (white blood cells).

Immunoglobulins are classified into five categories: IgA, IgD, IgE, IgG and IgM. And are distinguished by the type of heavy chain they contain. IgG molecules possess heavy chains known as γ-chains; IgMs have μ-chains; IgAs have α-chains; IgEs have ε-chains; and IgDs have δ-chains.

In this case, IgE is the immunoglobulin that attach to and sensitize mast cells and basophils.

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