What does the phrase “spiral of silence” mean as it is used in paragraph 5 ?

Ineed . read the passage, and choose the two (2) inferences that are most firmly based on the given information. experts have blamed caffeine for bone loss among older women. but a university study of 138 older women found that caffeine had no such effect. in that study, women who drank more than five cups of coffee a day had the same bone density as women who got little caffeine. 1. bone loss among older women is not a problem. 2. the experts who blamed caffeine for bone loss may be wrong. 3. caffeine causes healthy bones. 4. some older wome