If one does as Sri Krishna says i.e., meditating on His divya-mangaLa svarupa, then all sins are eliminated. Durguna-s of rāga dveṣa-s melt away. Indriya-s are subjugated. Mind is conquered & as a result experiencing Atma in purest form will happen uninterrupted
It should be interpreted as 'moving freely amidst external objects without any qualms'
आत्मा denotes Mind here
Very nature of Indriya-s is to experience external objects. One who wishes to be free of samsara keeps them under control. He lets them move freely for certain critical tasks needed for living [Eating, Breathing etc..]
But apart from that, indriya-s are fully subjugated
Same as (A)