Why they used (stating) not( state)...althought they was talking about fact?
, the most comprehensive effort at measuring public opinion across more than 100 countries, the proportion of respondents (stating) that “having a democratic political system” is a “bad” or “very bad” way to run the country,

Question

Answer

Because the verb in the quote from the respondents is in the infinitive, so the verb "state" is in the infinitive also. Sorry, English sucks.

Verpassen Sie nicht die Gelegenheit, bequem von zu Hause aus eine Sprache zu lernen. Stöbern Sie in unserer Auswahl an erfahrenen Sprachlehrern und melden Sie sich jetzt zu Ihrer ersten Unterrichtsstunde an!