The decreasing order of the acidity of the given compounds:

H₂O > ROH > HC ≡ CH

HC ≡ CH is less acidic because the carbon atoms here is sphybridized, so the electron density is higher on the carbon atom and therefore, the release of a proton is not easy. Thus, they are the least acidic compound among the given three compounds.

ROH is less acidic than water because of the alkyl group (electron releasing group).They do not favour the formation of alkoxide ion. Thus, decreases the acidic strength of the compound.

Water among the three given compounds is most acidic.