The Second Administrative Reforms Commission (2005) focused on reforms in institutional arrangements for good governance. This means that it aimed to improve the way government institutions are structured and operate, in order to promote efficient and effective governance.

Option 1, which is the correct answer, aligns with the stated objective of the commission. It implies that the commission was not concerned with specific reforms in the Indian Penal Code and the Criminal Justice System (option 2), nor was it focused on creating an ombudsman mechanism for reducing corruption in public life (option 3). Similarly, the commission did not primarily work on devising new measures for urban governance and management (option 4).

Therefore, option 1 best captures the main focus of the Second Administrative Reforms Commission (2005), which was to bring about reforms in the institutional arrangements for good governance.