The correct option is
A Respiratory diseases
SPM refers to the suspended Particulate Matter that is formed due to the accumulation of the dust, fumes, mist and smoke in the air. These are designated as PM 2.5, PM 5 and PM 10 according to the size of the suspended particles. The smallest particles can be breathed in easily into the respiratory tract. These are known for causing chronic respiratory diseases like asthma, bronchitis etc.
Hence, the correct answer is 'Respiratory diseases'