adding wife name in passport and change wife lastname to husband

[mgtech]

Hi..

I am applying for oci for my daugher ..but before htat i want to make sure
our names in passport are current..So

1. if i have to add wife name to my passport ...can i send photo copy
of marriage certificate?? is it ok or do i have to send original ...am not sure
if they going to return original ..what application i need to fill....planing to send via mail


2...how can my wife change her Last name to new(husbands) last name...does she has to submit original marriage certificate...?? ..and also original passport of both husband/wife..or jsut wife.??

THanks in advance..