Electronics can rust if their surface metals contain iron and are exposed to the atmosphere. Polyethylene, the chemical used in most plastic products, can protect metals from the atmosphere. Iron is non-reactive with polyethylene and polyethylene is readily available to electronics manufacturers. When the surfaces of electronics were treated with polyethylene coatings and exposed to the atmosphere, none of them became rusted during the period they were observed.
In deciding whether polyethylene coating would be useful in producing rust-free electronics for sale to consumers, it would be most helpful to determine which of the following?
【选项】
The proportion of users that are allergic to polyethylene
选项是否正确？