A municipal officer received Rs. 2 lakhs from a contractor as gratification for approving inflated bills for civic works. The officer has been charge-sheeted under Section 7 of PCA. Which statements are correct? Statement 1: The officer's conduct violates Section 7 of PCA as he took gratification for performing official duty. Statement 2: The contractor is also prosecuted as an abettor under Section 12 of PCA. Statement 3: The gratification amount must exceed Rs. 5 lakhs to constitute a Section 7 offence. Statement 4: The officer must prove legitimate source for the gratification received. Which statements are correct?