The correct answer is: Students who had early childhood education perform better academically than students who did not.
Indeed, although it is also true that early childhood education also benefits working parents who do not have to pay for childcare; that is a purely economic argument and the public is also very much concerned with the welfare and the advantages of such measure for their children. On the other hand if it turns out that it also makes children perform better in school, providing them with a qualitative advantage that is a more powerful argument for parents who want to ensure the possibility for their children to successfully earn a living in a very competitive world.
The other two arguments are actually detrimental to this claim as they declare that evidence is inconclusive and that such programs are not economically viable for most schools.