The correct answer is option 1: Rickets. Rickets is a condition caused by a deficiency of vitamin D, calcium, or phosphate. It is not directly related to smog or air pollution.

Option 2: Throat cancer can be caused by long-term exposure to air pollution, including smog. Inhalation of pollutants can irritate and damage the cells in the throat, leading to the formation of cancerous cells.

Option 3: Skin cancer is not directly caused by smog, but it can be indirectly influenced by air pollution. Air pollution can contribute to the formation of free radicals on the skin, which can damage DNA and increase the risk of skin cancer.

Option 4: Breathing problems, such as asthma and chronic obstructive pulmonary disease (COPD), can be caused or worsened by smog. Smog contains various pollutants, such as ozone and particulate matter, which can irritate the respiratory system and lead to breathing difficulties.

Therefore, the correct answer is option 1, as rickets is not caused by smog.