Since she believed _____ her abilities, she didn't ask _____ any help.
Explanation
Since she believed in her abilities, she didn't ask for any help.چونکہ اسے اپنی صلاحیتوں پر یقین تھا، اس لیے اس نے کسی سے مدد نہیں مانگی۔"Believed in" is the correct preposition to indicate confidence in abilities."Ask for" is used to indicate requesting help or assistance.