The correct option is B Both A and B
Acid rain and smog are more localized in nature and affect local regions with increased concentration of sulphur and nitrogen oxides. The most acidic rain has occurred over West Virginia, USA with a pH value of 1.5. The famous reducing smog was formed over London and called as London smog. Photochemical smog or oxidizing smog formed over Los Angeles and called as Los Angeles smog. Thus, the correct answer is option C.