Loss from staking in lotteries is a non-insurable risk. Non-insurable risks are risks that cannot be insured because they are considered too speculative or because the potential loss is too large. In the case of staking in lotteries, the outcome is entirely based on chance, and the likelihood of winning is extremely low. Therefore, the potential loss is much greater than the potential gain, making it a non-insurable risk. Insurance is designed to protect against risks that are measurable and can be predicted with some degree of certainty, such as fire, accidents, and burglary. Therefore, the correct answer to the question is "Loss from staking in lotteries".