The correct answer is B) After purchasing, the suit should be stowed in the storage bag in which it was received. This is the correct answer because immersion suits should be stored in their original packaging or storage bag in order to prevent damage to the suit and to maintain its integrity. Proper storage is crucial to ensuring the suit will function as intended in an emergency situation. The other options are incorrect: A) Lubricating the zipper with machine oil or mineral oil is not recommended, as this can degrade the zipper material over time. C) Immersion suits should not be worn during routine work on deck, as this can lead to unnecessary wear and tear. D) While a tear or leak would render the suit unserviceable, it does not necessarily mean the suit must be replaced, as repairs may be possible in some cases.