In the Lower Atmosphere,H₂SO₄ $\mathrm { H } _ { 2 }$

In the lower atmosphere,H₂SO₄ $\mathrm { H } _ { 2 }$ $\mathrm { SO } _ { 4 }$

A) is formed from photochemical reactions.
B) is related to the problem of acid deposition.
C) is a problem that only occurred during the first half of this century.
D) forms by a combination of O₂ and NO₂.
E) cannot form due to the density of the atmosphere.