Hybridisation of ' O′ in H2O is sp3 as it is having two lone pair and two sigma bond. Bond angle of sp3 hybridised compound should be 109.5∘. But in case of water, it is only 104.5∘ due to repulsion between the lone pairs. Lone pair-lone pair repulsion is higher than bond pair-bond pair repulsion. (VSEPR Theory)
So, both A and R are true and R is the correct explanation of A.