Statement A: Single chlorophyll a molecule forms the reaction centre.Statement B: In PS I the reaction centre chlorophyll a has an absorption peak at 700 nm while in PS II it has absorption maxima at 680 nm

Single chlorophyll a molecule forms the reaction centre. The reaction centre is different in both the photosystems. In PS I the reaction centre chlorophyll a has an absorption peak at 700 nm, hence is called P700, while in PS II it has absorption maxima at 680 nm, and is called P680.