It's B.) Water. Glucose [tex]{ C }_{ 6 }{ H }_{ 12 }{ O }_{ 6 }[/tex] and Oxygen [tex]{ O }_{ 2 }[/tex] gets in, Carbon dioxide [tex]{ CO }_{ 2 }[/tex] and water [tex]{ H }_{ 2 }O[/tex] comes out from the reaction.
[tex]{ C }_{ 6 }{ H }_{ 12 }{ O }_{ 6 }(s)+6{ O }_{ 2 }(g)\rightarrow 6C{ O }_{ 2 }(g)+6{ H }_{ 2 }O(l)+heat[/tex] is the exact reaction.