An Ombudsman-type body in India means an independent authority that investigates complaints against public officials, which later became the Lokpal at the Centre and Lokayukta in the states. Sorting the four options by chronology and purpose settles which one actually proposed this institution first.
Working backward from the later committees and movements to the earliest one confirms that the original recommendation came from the 1966 Administrative Reforms Commission.
Since all four options relate in some way to anti-corruption or administrative reform in India, the deciding factor is timing and the specific nature of what each one proposed, particularly whether it proposed an Ombudsman-style institution at all.
Moving from the most recent development back through the earlier ones shows that the 1966 Commission was the first to put forward this exact institutional design.
Hence, the correct answer is Administrative Reforms Commission, 1966.