The one with the greatest right of guardianship when giving a girl in Marriage

Question:

I am a woman in her thirties, and I am orphaned of both my parents, and I have no close (male) relatives apart from the following:
1. The son of my full paternal uncle (my sister's husband).
2. A maternal uncle, the full brother of my mother.
3. The sons of my sisters, who are adults.
4. The sons of my father's paternal uncles. Which one of them is a Mahram for me, and which of them has the right to give me away?

Answer:

The one with the greatest right of guardianship over you in marriage is your full paternal uncle's son, since he is the closest paternal relative, according to what you have mentioned in the question. As for your maternal uncle and the sons of your sister's, they are not guardians in marriage, because they are not paternal relatives, all though they are Mahrams for you. As for the sons of your father's paternal uncle they are guardians for you in marriage after your full parental uncles's son, but they are not Mahrams for you, because it is permissible for each one of them to marry you, if there is no obejection due to a fostering relationship or a relationship by marriage.

Source:
Shaykh `Abdul-`Azeez Bin Baz
Fatawa Islamiyah Darussalam Vol: 5 page no .247