which statement(s) about docking are true? which statement(s) about docking are true? in rigid docking both ligand and receptor atoms/bonds are restrained/do not rotate in rigid docking ligand atoms/bonds are allowed to rotate and receptor atoms/bonds are restrained/do not rotate in flexible docking ligand atoms/bonds are allowed to rotate and receptor atoms/bonds are restrained/rigid in flexible docking both ligand atoms/bonds and receptor atoms/bonds are allowed to rotate