Explanation:

- Ganesh's mother's brother is his maternal uncle.

- His uncle's father is also Ganesh's maternal grandfather.

- The granddaughter of Ganesh's maternal grandfather could be Ganesh himself if he is a boy, or could be Ganesh’s sister or cousin.

- If Ganesh is the granddaughter, he is walking with himself, which is not possible, so it must be his sister or cousin.

Considering Ganesh is male, and he walks with a female cousin (as his own sister fits the criteria of being a granddaughter too):

- Option 1: Daughter – incorrect, as the relationship doesn't match.

- Option 2: Mother – incorrect, as it doesn’t fit the definition of granddaughter.

- Option 3: Cousin – correct, as his uncle's father's granddaughter can be his cousin.

- Option 4: Granddaughter – incorrect, does not fit the context.

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