An executrix of an estate is:

An executrix of an estate refers specifically to a female appointed to administer the estate of a deceased person according to the terms of the decedent's will. This individual is typically named in the will itself, indicating that the decedent entrusted her with this responsibility. The role involves managing the estate, settling debts, distributing assets, and ensuring that the wishes outlined in the will are carried out correctly.

While it is indeed true that the court may appoint an executrix if the decedent did not name one in the will, the defining aspect of the executrix's role is that she is specifically named by the decedent, thus making option B the most accurate choice. Being a financial advisor or a relative of the decedent does not inherently establish the authority or role of an executrix, which is explicitly defined by the will.