Concept:Concentrated tetraoxosulphate(VI) acid,
H2SO4, causes chemical burns, so the first action is to dilute and remove it from the skin safely.
Explanation:Wash the affected skin immediately with plenty of cool running water.
Cool water dilutes the acid and washes it away without adding extra heat.
Do not use sodium hydroxide solution because neutralising a strong acid with a strong alkali produces a violent exothermic reaction that can worsen the burn.
Do not use iodine or sodium trioxonitrate(V) solution; they do not treat acid burns and may cause further irritation.
Continue rinsing with cool running water for several minutes to reduce damage.
Answer:A. with cool running water