The correct answer is Standard_Big because that label is not a recognized Azure VM size.

Azure VM sizes use a structured naming pattern that includes a series letter, a numeric size, and optional suffixes that indicate optimized features and generation. For example the D, E, and F series use names like Standard_D2s_v3 and Standard_E2s_v4. The label Standard_Big does not follow the documented pattern and it does not appear in the official sizes list.

Standard_D2s_v3 is a valid Azure VM size in the Dv3 series and it therefore is not the correct answer to this question.

Standard_E2s_v4 is a valid Azure VM size in the Ev4 series and it therefore is not the correct answer to this question.

Standard_F2s matches the naming pattern for the F series of VMs and it is a recognized size so it is not the correct answer.

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