Consider the following statements in respect of flow equalization in a wastewater treatment plant:1. Biological treatment is enhanced because shock loadings are eliminated or minimized.2. Flow equalization is an attractive option for upgrading the performance of overloaded treatment plants.3. Inhibiting substances can be diluted and pH can be stabilized.4. Thickening performance of primary sedimentation tanks following grit removal is improved.Which of the above statements are correct?

• A. 1, 2, 3 and 4
• B. 1, 2 and 3 only
• C. 1, 2 and 4 only
• D. 3 and 4 only