The answer is Ten. There are 9 "e's" in the sentence with the blank spot but once the correct answer is added it varies. So when you add "ten" there becomes 10 totals "e's".
ten because of the letter 'e' in 10 as well.
If you choose nine then there are ten 'e's
if you choose eleven then there are 12 'e's
IF you choose twelve then there are 11 'e's
and if you choose ten then there are 10 'e's
If you choose nine then there are ten 'e's
if you choose eleven then there are 12 'e's
IF you choose twelve then there are 11 'e's
and if you choose ten then there are 10 'e's