The correct option is A 1-Alkyne > Alkene > Alkane
R−C≡CH→R−C≡C−
R−CH=CH2→R−CH=CH−
R−CH2−CH3→R−CH2CH−2
Stability of conjugate base ∝ Acidity strength
The formation of C - H bond in acetylene involves sp-hybridised carbon atom. Since s-electrons are closer to the nucleus than p electrons, sp hybrid orbitals are more electronegative through its smaller(in length) and thicker lobes which increases the time spent by electrons near nucleus than in sp2 and sp3. Thus, the electrons present in a bond having more s-character will be more closer to the nucleus.
s-character ∝ Electronegativity ∝ Stability of conjugate base
Alkyne has sp carbon which is more electronegative which will stabilise the conjugate base formed.
Alkene sp2 has less s character than alkyne so its conjugate base is less stable than alkyne.
Alkane sp3 has least s character. Thus its conjugate base is least stabiled.