The effectiveness of ear muffs can be impacted by factors such as eyeglasses, long hair, and the seal around the outer ear. Proper sealing is crucial for reducing noise. Hence, the answer is 'All of the above.' ;
The effectiveness of ear muffs can be influenced by eyeglasses, long hair, and the seal around the outer ear. Each of these factors can create gaps or interfere with the fit, reducing noise-blocking capabilities. Therefore, the correct answer to the question is 'All of the above.'
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