Only waste paper qualifies as biomass among the options given. Biomass includes organic material, while plastic, metal, and chemical items do not fit this definition. Therefore, Elaine can indeed use waste paper as biomass. ;
Elaine can use waste paper as biomass since it is organic and biodegradable. The other options, such as metal vases, plastic dishes, expired cleaners, and old batteries, do not qualify as biomass. Therefore, the correct option is E. waste paper.
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