ACCorDing to thE lECturE, whAt wErE thE sCiEntiFiC instrumEnts usED in stuDying hAllEy’sComEt in 19867 A、two spACECrAFt lAunChED、By thE soviEt union. B、two spACECrAFt lAunChED By jApAn. C、onE spACECrAFt lAunChED ByAmEriC A、 D、thE giotto lAunChED ByEuropEAn spACEAgEnCy.