You seem to misinterpret the question - which happens easily since in many cases it's just about tiny nuances of the question or answer making one correct or incorrect.

While the employee's previous experiences are indeed added as lines in the resume, in this case the question is about [...] add more information [...] within the(ir) resumé. This additional information in fact can be added in the description field of a resume line item (here, 'Horticulturist, commercial'):