Year Zero

[Agent Smith]

She's 25 years old.

 

[The Highlander]

Let us assume that a girl was born in $\displaystyle 2000$. How old should she be in $\displaystyle 2025$, according to the old calendar?
(a) $\displaystyle 24$ years old
(b) $\displaystyle 25$ years old
(c) $\displaystyle 26$ years old
Assume that she completed a perfect circle.

She's 25 years old.

It seems to me that none of the options provided give a correct answer (unless "Assume that she completed a perfect circle." means on her birth date at the (exact) hour of her birth. ).

In the year 2025 she will be both 24 and 25 years old; 24 before her birthday and 25 on/after it.