Clearly true and impossible to argue against.
“The benefits of adding more green space to the city are undeniable.”
“It is undeniable that the first option would attract more visitors to the area.”
Use 'undeniable' in Task 2 when presenting a benefit so obvious that it strengthens your argument without much extra justification, such as 'the benefits are undeniable'. It works especially well right before you state your final recommendation.
Synonyms: indisputable, unquestionable, incontestable