After reading the paragraph below, answer the questions that follow.
Plants are sometimes used for phytoremediation in areas where the soil has been contaminated with heavy metals. Suppose the Acme Remediation Company is proposing to remediate a contaminated area that you wish to restore. Acme presents you with the following data as evidence of their company's ability to remediate soil.

The data provide evidence for which of the following?
◦ The copper removal percentage was approximately doubled by the presence of the plants used to remediate the soil.
◦ Phytoremediation is especially effective at removing zinc from the soil.
◦ The most toxic product in the soil is lead.
◦ Before restoration efforts, there was twice as much lead in the soil as cadmium.