Question

it is believed that in slowing bone turnover, the drugs may ______ the repair of normally occurring microfractures and eventually result in a major fracture. source: new york times amaze pummel simper impede

Explanation:

The context indicates that drugs, by slowing bone turnover, have a negative impact on micro - fracture repair leading to major fractures. "Impede" means to hinder or obstruct, which fits this context. "Amaze" means to surprise greatly, "pummel" means to hit repeatedly, and "simper" means to smile in an affected way. None of these other words make sense in the given context.

Answer:

D. impede