The argument is based on a study by Lance Hosey, whose findings claim that aromatic oils help dispel patients’ anxiety, the aroma of lavender may alleviate post-operative pain, and herbal scents such as rosemary may boost cognitive activity in Alzheimer’s patients.
Therefore, the therapeutic value of nature’s aromatics bolsters the argument for the integration of herbs and flowers into urban planning.
However the study don't describe anything beyond the stated information, so concluding that all natural herbs and flowers is therapeutic is somewhere flawed. We can eliminate A and B.
In C, The conclusion don't re-state the words introduced in argument premise. If it had been, the conclusion would had stated about the said aromatic oil and scents, not generalizing all.
There is no choice given in the argument to choose in between any institutional or urban setting, nor argument background is drawn scaling such comparison. D Out
E is the answer because the conclusion don't backup its statement with any preceding premise or statement.