<em>Correct answer (assuming question was written around 2004 or 2008): </em>
B. In the 2000 presidential election, Florida had 25 electoral votes. Now it has 27 electoral votes because the census determined that the state's population had increased.
In my response, I noted the 2004 or 2008 presidential elections, because in those election cycles Florida had 27 electoral votes, determined by census numbers of the shifting balance of US population. In the 2012 and 2016 presidential elections, Florida had 29 electoral votes, as its population continued to increase relative to other states. That number will remain in place for the 2020 election. After that, the 2020 Census will determine new numbers for the Electoral College once again.
Here's what the National Archives says concerning how Electoral College delegates are assigned: <em>Electoral votes are allocated among the states based on the Census. Every state is allocated a number of votes equal to the number of senators and representatives in its U.S. Congressional delegation—two votes for its senators in the U.S. Senate plus a number of votes equal to the number of its members in the U. S. House of Representatives.</em>
So the number of electoral votes each state gets (of the 538 total electoral votes) is recalculated every ten years, based on the most recent US Census data.